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Segreti A, Celeski M, Guerra E, Crispino SP, Vespasiano F, Buzzelli L, Fossati C, Papalia R, Pigozzi F, Grigioni F. Effects of Environmental Conditions on Athlete's Cardiovascular System. J Clin Med 2024; 13:4961. [PMID: 39201103 PMCID: PMC11355938 DOI: 10.3390/jcm13164961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2024] [Revised: 08/13/2024] [Accepted: 08/17/2024] [Indexed: 09/02/2024] Open
Abstract
Environmental factors such as extreme temperatures, humidity, wind, pollution, altitude, and diving can significantly impact athletes' cardiovascular systems, potentially hindering their performance, particularly in outdoor sports. The urgency of this issue is heightened by the increasing prevalence of climate change and its associated conditions, including fluctuating pollution levels, temperature variations, and the spread of infectious diseases. Despite its critical importance, this topic is often overlooked in sports medicine. This narrative review seeks to address this gap by providing a comprehensive, evidence-based evaluation of how athletes respond to environmental stresses. A thorough assessment of current knowledge is essential to better prepare athletes for competition under environmental stress and to minimize the harmful effects of these factors. Specifically, adaptative strategies and preventative measures are vital to mitigating these environmental influences and ensuring athletes' safety.
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Affiliation(s)
- Andrea Segreti
- Cardiology Unit, Fondazione Policlinico Universitario Campus Bio-Medico, Via Alvaro del Portillo, 200, 00128 Roma, Italy; (M.C.); (S.P.C.); (F.V.); (L.B.); (F.G.)
- Research Unit of Cardiovascular Science, Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Roma, Italy
- Department of Movement, Human and Health Sciences, University of Rome “Foro Italico”, Piazza Lauro de Bosis, 15, 00135 Roma, Italy; (C.F.); (F.P.)
| | - Mihail Celeski
- Cardiology Unit, Fondazione Policlinico Universitario Campus Bio-Medico, Via Alvaro del Portillo, 200, 00128 Roma, Italy; (M.C.); (S.P.C.); (F.V.); (L.B.); (F.G.)
- Research Unit of Cardiovascular Science, Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Roma, Italy
| | - Emiliano Guerra
- Cardiology Division, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Policlinico di Modena, Via del Pozzo, 71, 41124 Modena, Italy;
| | - Simone Pasquale Crispino
- Cardiology Unit, Fondazione Policlinico Universitario Campus Bio-Medico, Via Alvaro del Portillo, 200, 00128 Roma, Italy; (M.C.); (S.P.C.); (F.V.); (L.B.); (F.G.)
- Research Unit of Cardiovascular Science, Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Roma, Italy
| | - Francesca Vespasiano
- Cardiology Unit, Fondazione Policlinico Universitario Campus Bio-Medico, Via Alvaro del Portillo, 200, 00128 Roma, Italy; (M.C.); (S.P.C.); (F.V.); (L.B.); (F.G.)
- Research Unit of Cardiovascular Science, Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Roma, Italy
| | - Lorenzo Buzzelli
- Cardiology Unit, Fondazione Policlinico Universitario Campus Bio-Medico, Via Alvaro del Portillo, 200, 00128 Roma, Italy; (M.C.); (S.P.C.); (F.V.); (L.B.); (F.G.)
- Research Unit of Cardiovascular Science, Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Roma, Italy
| | - Chiara Fossati
- Department of Movement, Human and Health Sciences, University of Rome “Foro Italico”, Piazza Lauro de Bosis, 15, 00135 Roma, Italy; (C.F.); (F.P.)
| | - Rocco Papalia
- Department of Orthopaedic and Trauma Surgery, Università Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Roma, Italy;
- Research Unit of Orthopaedic and Trauma Surgery, Fondazione Policlinico Universitario Campus Bio-Medico, Via Alvaro del Portillo, 200, 00128 Roma, Italy
| | - Fabio Pigozzi
- Department of Movement, Human and Health Sciences, University of Rome “Foro Italico”, Piazza Lauro de Bosis, 15, 00135 Roma, Italy; (C.F.); (F.P.)
| | - Francesco Grigioni
- Cardiology Unit, Fondazione Policlinico Universitario Campus Bio-Medico, Via Alvaro del Portillo, 200, 00128 Roma, Italy; (M.C.); (S.P.C.); (F.V.); (L.B.); (F.G.)
- Research Unit of Cardiovascular Science, Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Roma, Italy
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Declercq L, Bouten J, Van Dyck M, Boone J, Derave W, Heyse B, Bourgois JG. A dive into the physiological responses to maximal apneas, O 2 and CO 2 tables in apnea novices. Eur J Appl Physiol 2024:10.1007/s00421-024-05563-7. [PMID: 39044031 DOI: 10.1007/s00421-024-05563-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Accepted: 07/09/2024] [Indexed: 07/25/2024]
Abstract
PURPOSE Apnea duration is dependent on three factors: oxygen storage, oxygen consumption, hypoxia and hypercapnia tolerance. While current literature focuses on maximal apneas to improve apnea duration, apnea trained individuals use timed-repeated submaximal apneas, called "O2 and CO2 tables". These tables claim to accommodate the body to cope with hypoxia and hypercapnia, respectively. The aim of this study was twofold. First, to investigate the determinants of maximal apnea duration in apnea novices. Second, to compare physiologic responses to maximal apneas, O2 and CO2 tables. METHODS After medical screening, lung function test and hemoglobin mass measurement, twenty-eight apnea novices performed three apnea protocols in random order: maximal apneas, O2 table and CO2 table. During apnea, peripheral oxygen saturation (SpO2), heart rate (HR), muscle (mTOI) and cerebral (cTOI) tissue oxygenation index were measured continuously. End-tidal carbon dioxide (EtCO2) was measured before and after apneas. RESULTS Larger lung volumes, higher resting cTOI and lower resting EtCO2 levels correlated with longer apnea durations. Maximal apneas induced greater decreases in SpO2 (- 16%) and cTOI (- 13%) than O2 (- 8%; - 8%) and CO2 tables (- 6%; - 6%), whereas changes in EtCO2, HR and mTOI did not differ between protocols. CONCLUSION These results suggest that, in apnea novices, O2 and CO2 tables did not induce a more profound hypoxia and hypercapnia, but a similar reduction in oxygen consumption than maximal apneas. Therefore, apnea novices should mainly focus on maximal apneas to improve hypoxia and hypercapnia tolerance. The use of specific lung training protocols can help to increase oxygen storage capacity.
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Affiliation(s)
- Louise Declercq
- Department of Movement and Sports Sciences, Ghent University, Watersportlaan 2, 9000, Ghent, Belgium
| | - Janne Bouten
- Department of Movement and Sports Sciences, Ghent University, Watersportlaan 2, 9000, Ghent, Belgium
- Laboratory of Sport, Expertise and Performance (EA 7370), French Institute of Sport (INSEP), Paris, France
| | - Matthew Van Dyck
- Department of Movement and Sports Sciences, Ghent University, Watersportlaan 2, 9000, Ghent, Belgium
| | - Jan Boone
- Department of Movement and Sports Sciences, Ghent University, Watersportlaan 2, 9000, Ghent, Belgium
| | - Wim Derave
- Department of Movement and Sports Sciences, Ghent University, Watersportlaan 2, 9000, Ghent, Belgium
| | - Bjorn Heyse
- Department of Anesthesiology, Ghent University Hospital, Corneel Heymanslaan 10, 9000, Ghent, Belgium
| | - Jan G Bourgois
- Department of Movement and Sports Sciences, Ghent University, Watersportlaan 2, 9000, Ghent, Belgium.
- Centre of Sports Medicine, Ghent University Hospital, Corneel Heymanslaan 10, 9000, Ghent, Belgium.
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Bezruk D, Bahenský P, Marko D, Krajcigr M, Bahenský P, Novák-Nowická E, Mrkvička T. The Effect of Static Apnea Diving Training on the Physiological Parameters of People with a Sports Orientation and Sedentary Participants: A Pilot Study. Sports (Basel) 2024; 12:140. [PMID: 38921834 PMCID: PMC11209488 DOI: 10.3390/sports12060140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Revised: 05/17/2024] [Accepted: 05/18/2024] [Indexed: 06/27/2024] Open
Abstract
Diver training improves physical and mental fitness, which can also benefit other sports. This study investigates the effect of eight weeks of static apnea training on maximum apnea time, and on the physiological parameters of runners, swimmers, and sedentary participants, such as forced vital capacity (FVC), minimum heart rate (HR), and oxygen saturation (SpO2). The study followed 19 participants, including five runners, swimmers, sedentary participants, and four competitive divers for reference values. The minimum value of SpO2, HR, maximum duration of apnea, and FVC were measured. Apnea training occurred four times weekly, consisting of six apneas with 60 s breathing pauses. Apnea duration was gradually increased by 30 s. The measurement started with a 30 s apnea and ended with maximal apnea. There was a change in SpO2 decreased by 6.8%, maximum apnea length increased by 15.8%, HR decreased by 9.1%, and FVC increased by 12.4% for the groups (p < 0.05). There were intra-groups changes, but no significant inter-groups difference was observed. Eight weeks of apnea training improved the maximum duration of apnea, FVC values and reduced the minimum values of SpO2 and HR in all groups. No differences were noted between groups after training. This training may benefit cardiorespiratory parameters in the population.
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Affiliation(s)
- Dmitriy Bezruk
- Department of Sports Studies, Faculty of Education, University of South Bohemia in České Budějovice, 37005 České Budějovice, Czech Republic; (D.B.); (D.M.); (M.K.); (P.B.J.); (E.N.-N.)
| | - Petr Bahenský
- Department of Sports Studies, Faculty of Education, University of South Bohemia in České Budějovice, 37005 České Budějovice, Czech Republic; (D.B.); (D.M.); (M.K.); (P.B.J.); (E.N.-N.)
| | - David Marko
- Department of Sports Studies, Faculty of Education, University of South Bohemia in České Budějovice, 37005 České Budějovice, Czech Republic; (D.B.); (D.M.); (M.K.); (P.B.J.); (E.N.-N.)
| | - Miroslav Krajcigr
- Department of Sports Studies, Faculty of Education, University of South Bohemia in České Budějovice, 37005 České Budějovice, Czech Republic; (D.B.); (D.M.); (M.K.); (P.B.J.); (E.N.-N.)
| | - Petr Bahenský
- Department of Sports Studies, Faculty of Education, University of South Bohemia in České Budějovice, 37005 České Budějovice, Czech Republic; (D.B.); (D.M.); (M.K.); (P.B.J.); (E.N.-N.)
| | - Eva Novák-Nowická
- Department of Sports Studies, Faculty of Education, University of South Bohemia in České Budějovice, 37005 České Budějovice, Czech Republic; (D.B.); (D.M.); (M.K.); (P.B.J.); (E.N.-N.)
| | - Tomáš Mrkvička
- Department of Applied Mathematics and Informatics, Faculty of Economics, University of South Bohemia in České Budějovice, 37005 České Budějovice, Czech Republic;
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Kjeld T, Krag TO, Brenøe A, Møller AM, Arendrup HC, Højberg J, Fuglø D, Hancke S, Tolbod LP, Gormsen LC, Vissing J, Hansen EG. Hemoglobin concentration and blood shift during dry static apnea in elite breath hold divers. Front Physiol 2024; 15:1305171. [PMID: 38745836 PMCID: PMC11092981 DOI: 10.3389/fphys.2024.1305171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Accepted: 01/23/2024] [Indexed: 05/16/2024] Open
Abstract
Introduction Elite breath-hold divers (BHD) enduring apneas of more than 5 min are characterized by tolerance to arterial blood oxygen levels of 4.3 kPa and low oxygen-consumption in their hearts and skeletal muscles, similar to adult seals. Adult seals possess an adaptive higher hemoglobin-concentration and Bohr effect than pups, and when sedated, adult seals demonstrate a blood shift from the spleen towards the brain, lungs, and heart during apnea. We hypothesized these observations to be similar in human BHD. Therefore, we measured hemoglobin- and 2,3-biphosphoglycerate-concentrations in BHD (n = 11) and matched controls (n = 11) at rest, while myocardial mass, spleen and lower extremity volumes were assessed at rest and during apnea in BHD. Methods and results After 4 min of apnea, left ventricular myocardial mass (LVMM) determined by 15O-H2O-PET/CT (n = 6) and cardiac MRI (n = 6), was unaltered compared to rest. During maximum apnea (∼6 min), lower extremity volume assessed by DXA-scan revealed a ∼268 mL decrease, and spleen volume, assessed by ultrasonography, decreased ∼102 mL. Compared to age, BMI and VO2max matched controls (n = 11), BHD had similar spleen sizes and 2,3- biphosphoglycerate-concentrations, but higher total hemoglobin-concentrations. Conclusion Our results indicate: 1) Apnea training in BHD may increase hemoglobin concentration as an oxygen conserving adaptation similar to adult diving mammals. 2) The blood shift during dry apnea in BHD is 162% more from the lower extremities than from the spleen. 3) In contrast to the previous theory of the blood shift demonstrated in sedated adult seals, blood shift is not towards the heart during dry apnea in humans.
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Affiliation(s)
- Thomas Kjeld
- Copenhagen Neuromuscular Center, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Thomas O. Krag
- Copenhagen Neuromuscular Center, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Anders Brenøe
- Department of Clinical Medicine, Panum Institute, University of Copenhagen, Copenhagen, Denmark
| | - Ann Merete Møller
- Department of Anesthesiology, Herlev Hospital, University of Copenhagen, Copenhagen, Denmark
| | | | - Jens Højberg
- Department of Cardiothoracic Anesthesiology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Dan Fuglø
- Department of Nuclear Medicine, Herlev Hospital, University of Copenhagen, Copenhagen, Denmark
| | - Søren Hancke
- Department of Clinical Medicine, Panum Institute, University of Copenhagen, Copenhagen, Denmark
| | - Lars Poulsen Tolbod
- Department of Nuclear Medicine and PET Centre, Aarhus University Hospital, Aarhus, Denmark
| | - Lars Christian Gormsen
- Department of Nuclear Medicine and PET Centre, Aarhus University Hospital, Aarhus, Denmark
| | - John Vissing
- Copenhagen Neuromuscular Center, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Egon Godthaab Hansen
- Department of Anesthesiology, Herlev Hospital, University of Copenhagen, Copenhagen, Denmark
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Saiko G, Burton T, Kakihana Y, Hatanaka K, Takahito O, Douplik A. Observation of blood motion in the internal jugular vein by contact and contactless photoplethysmography during physiological testing: case studies. BIOMEDICAL OPTICS EXPRESS 2024; 15:2578-2589. [PMID: 38633071 PMCID: PMC11019709 DOI: 10.1364/boe.516609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 02/03/2024] [Accepted: 02/03/2024] [Indexed: 04/19/2024]
Abstract
Central venous pressure is an estimate of right atrial pressure and is often used to assess hemodynamic status. However, since it is measured invasively, non-invasive alternatives would be of great utility. The aim of this preliminary study was a) to investigate whether photoplethysmography (PPG) can be used to characterize venous system fluid motion and b) to find the model for venous blood volume modulations. For this purpose, we monitored the internal jugular veins using contact (cPPG) and video PPG during clinically validated physiological tests: abdominojugular test (AJT) and breath holding (BH). Video PPG and cPPG signals were captured simultaneously on the left and right sides of the neck, respectively. ECG was also captured using the same clinical monitor as cPPG. Two volunteers underwent AJT and BH with head up/down, each with: baseline (15s), experiment (15s), and recovery (15s). Video PPG was split into remote PPG (rPPG) and micromotion detection. All signal modalities were significantly affected by physiological testing. Moreover, cPPG and micromotion waveforms exhibited primary features of jugular vein waveforms and, therefore, have great potential for venous blood flow monitoring. Specifically, remote patient monitoring applications may be enabled by this methodology, facilitating physical collection without a specially trained care provider.
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Affiliation(s)
- Gennadi Saiko
- Dept. of Physics, Toronto Metropolitan University, Toronto, Canada
| | - Timothy Burton
- Dept. of Biomedical Engineering, Toronto Metropolitan University, Toronto, Canada
| | - Yasuyuki Kakihana
- Dept. of Emergency and Intensive Care Medicine, Kagoshima University, Kagoshima, Japan
| | - Kosaku Hatanaka
- Dept. of Emergency and Intensive Care Medicine, Kagoshima University, Kagoshima, Japan
| | - Ohtonari Takahito
- Dept. of Emergency and Intensive Care Medicine, Kagoshima University, Kagoshima, Japan
| | - Alexandre Douplik
- Dept. of Physics, Toronto Metropolitan University, Toronto, Canada
- iBEST, Toronto Metropolitan University, Toronto, Canada
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Ribeiro LDJA, Bastos VHDV, Coertjens M. Breath-holding as model for the evaluation of EEG signal during respiratory distress. Eur J Appl Physiol 2024; 124:753-760. [PMID: 38105311 DOI: 10.1007/s00421-023-05379-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 11/14/2023] [Indexed: 12/19/2023]
Abstract
PURPOSE Research describes the existence of a relationship between cortical activity and the regulation of bulbar respiratory centers through the evaluation of the electroencephalographic (EEG) signal during respiratory challenges. For example, we found evidences of a reduction in the frequency of the EEG (alpha band) in both divers and non-divers during apnea tests. For instance, this reduction was more prominent in divers due to the greater physiological disturbance resulting from longer apnea time. However, little is known about EEG adaptations during tests of maximal apnea, a test that voluntarily stops breathing and induces dyspnea. RESULTS Through this mini-review, we verified that a protocol of successive apneas triggers a significant increase in the maximum apnea time and we hypothesized that successive maximal apnea test could be a powerful model for the study of cortical activity during respiratory distress. CONCLUSION Dyspnea is a multifactorial symptom and we believe that performing a successive maximal apnea protocol is possible to understand some factors that determine the sensation of dyspnea through the EEG signal, especially in people not trained in apnea.
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Affiliation(s)
- Lucas de Jesus Alves Ribeiro
- Physiotherapy Department, Universidade Federal do Delta do Parnaíba, Av. São Sebastião, CEP: 64.202-020, Parnaíba, PI, 2819, Brazil
- Brain Mapping and Functionality Laboratory, Universidade Federal do Delta do Parnaíba, Piauí, Brazil
| | - Victor Hugo do Vale Bastos
- Physiotherapy Department, Universidade Federal do Delta do Parnaíba, Av. São Sebastião, CEP: 64.202-020, Parnaíba, PI, 2819, Brazil
- Postgraduate Program in Biomedical Sciences, Universidade Federal do Delta do Parnaíba, Piauí, Brazil
- Brain Mapping and Functionality Laboratory, Universidade Federal do Delta do Parnaíba, Piauí, Brazil
| | - Marcelo Coertjens
- Physiotherapy Department, Universidade Federal do Delta do Parnaíba, Av. São Sebastião, CEP: 64.202-020, Parnaíba, PI, 2819, Brazil.
- Postgraduate Program in Biomedical Sciences, Universidade Federal do Delta do Parnaíba, Piauí, Brazil.
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7
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Rixen M, Weickmann J, Gebauer RA, Weidenbach M, Markel F, Michaelis A, Dähnert I, Wüstenfeld J, Münch D, Poschart M, Sieber A, Schagatay E, Paech C. First Real-Life Data on the Diving Response in Healthy Children. Pediatr Cardiol 2024; 45:314-322. [PMID: 38177487 DOI: 10.1007/s00246-023-03370-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 11/30/2023] [Indexed: 01/06/2024]
Abstract
Swimming and diving are popular recreational activities, representing an effective option in maintaining and improving cardiovascular fitness in healthy people. To date, only little is known about the cardiovascular adaption to submersion in children. This study was conducted to improve an understanding thereof. We used a stepwise apnea protocol with apnea at rest, apnea with facial immersion, and at last apnea during whole body submersion. Continuous measurement of heart rate, oxygen saturation, and peripheral resistance index was done. Physiologic data and analysis of influencing factors on heart rate, oxygen saturation, and peripheral vascular tone response are reported. The current study presents the first data of physiologic diving response in children. Data showed that facial or whole body submersion leads to a major drop in heart rate, and increase of peripheral resistance, while the oxygen saturation seems to be unaffected by static apnea in most children, with apnea times of up to 75 s without change in oxygen saturation.
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Affiliation(s)
- Mareike Rixen
- Department for Pediatric Cardiology, University of Leipzig - Heart Center, Strümpellstr. 39, 04289, Leipzig, Germany
| | - Johannes Weickmann
- Department for Pediatric Cardiology, University of Leipzig - Heart Center, Strümpellstr. 39, 04289, Leipzig, Germany
| | - Roman Antonin Gebauer
- Department for Pediatric Cardiology, University of Leipzig - Heart Center, Strümpellstr. 39, 04289, Leipzig, Germany
| | - Michael Weidenbach
- Department for Pediatric Cardiology, University of Leipzig - Heart Center, Strümpellstr. 39, 04289, Leipzig, Germany
| | - Franziska Markel
- Department for Pediatric Cardiology, University of Leipzig - Heart Center, Strümpellstr. 39, 04289, Leipzig, Germany
| | - Anna Michaelis
- Department for Pediatric Cardiology, University of Leipzig - Heart Center, Strümpellstr. 39, 04289, Leipzig, Germany
| | - Ingo Dähnert
- Department for Pediatric Cardiology, University of Leipzig - Heart Center, Strümpellstr. 39, 04289, Leipzig, Germany
| | - Jan Wüstenfeld
- Department of Sports Medicine, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt Universität Zu Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
- Institut for Applied Training Science, Marschnerstrasse 29, Leipzig, Germany
| | - David Münch
- Landestauchsportverband Sachsen E.V, Am Sportforum 3, 04105, Leipzig, Germany
| | - Max Poschart
- SC DHfK Leipzig E.V, Am Sportforum 10, 04105, Leipzig, Germany
| | - Arne Sieber
- Oxygen Scientific GmbH, Eichbachgasse 151, 8041, Graz, Austria
| | - Erika Schagatay
- Environmental Physiology Group, Department of Health Sciences, Mid Sweden University, Östersund, Sweden
| | - Christian Paech
- Department for Pediatric Cardiology, University of Leipzig - Heart Center, Strümpellstr. 39, 04289, Leipzig, Germany.
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8
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Barwood MJ, Eglin C, Hills SP, Johnston N, Massey H, McMorris T, Tipton MJ, Wakabayashi H, Webster L. Habituation of the cold shock response: A systematic review and meta-analysis. J Therm Biol 2024; 119:103775. [PMID: 38211547 DOI: 10.1016/j.jtherbio.2023.103775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 11/27/2023] [Accepted: 12/01/2023] [Indexed: 01/13/2024]
Abstract
Cold water immersion (CWI) evokes the life-threatening reflex cold shock response (CSR), inducing hyperventilation, increasing cardiac arrhythmias, and increasing drowning risk by impairing safety behaviour. Repeated CWI induces CSR habituation (i.e., diminishing response with same stimulus magnitude) after ∼4 immersions, with variation between studies. We quantified the magnitude and coefficient of variation (CoV) in the CSR in a systematic review and meta-analysis with search terms entered to Medline, SportDiscus, PsychINFO, Pubmed, and Cochrane Central Register. Random effects meta-analyses, including effect sizes (Cohen's d) from 17 eligible groups (k), were conducted for heart rate (HR, n = 145, k = 17), respiratory frequency (fR, n = 73, k = 12), minute ventilation (Ve, n = 106, k = 10) and tidal volume (Vt, n = 46, k=6). All CSR variables habituated (p < 0.001) with large or moderate pooled effect sizes: ΔHR -14 (10) bt. min-1 (d: -1.19); ΔfR -8 (7) br. min-1 (d: -0.78); ΔVe, -21.3 (9.8) L. min-1 (d: -1.64); ΔVt -0.4 (0.3) L -1. Variation was greatest in Ve (control vs comparator immersion: 32.5&24.7%) compared to Vt (11.8&12.1%). Repeated CWI induces CSR habituation potentially reducing drowning risk. We consider the neurophysiological and behavioural consequences.
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Affiliation(s)
- Martin J Barwood
- Faculty of Social and Health Sciences, Leeds Trinity University, Horsforth, UK.
| | - Clare Eglin
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, UK
| | - Samuel P Hills
- Faculty of Health and Social Sciences, Bournemouth University, Bournemouth, UK
| | - Nicola Johnston
- Faculty of Social and Health Sciences, Leeds Trinity University, Horsforth, UK
| | - Heather Massey
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, UK
| | - Terry McMorris
- Department of Sport and Exercise Science, Institute for Sport, University of Chichester, College Lane, Chichester, West Sussex, UK
| | - Michael J Tipton
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, UK
| | - Hitoshi Wakabayashi
- Laboratory of Environmental Ergonomics, Faculty of Engineering, Hokkaido University, Sapporo, Japan
| | - Lisa Webster
- Faculty of Social and Health Sciences, Leeds Trinity University, Horsforth, UK
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9
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Mulder E, Staunton C, Sieber A, Schagatay E. Unlocking the depths: multiple factors contribute to risk for hypoxic blackout during deep freediving. Eur J Appl Physiol 2023; 123:2483-2493. [PMID: 37300699 PMCID: PMC10615935 DOI: 10.1007/s00421-023-05250-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 06/01/2023] [Indexed: 06/12/2023]
Abstract
PURPOSE To examine the effect of freediving depth on risk for hypoxic blackout by recording arterial oxygen saturation (SpO2) and heart rate (HR) during deep and shallow dives in the sea. METHODS Fourteen competitive freedivers conducted open-water training dives wearing a water-/pressure proof pulse oximeter continuously recording HR and SpO2. Dives were divided into deep (> 35 m) and shallow (10-25 m) post-hoc and data from one deep and one shallow dive from 10 divers were compared. RESULTS Mean ± SD depth was 53 ± 14 m for deep and 17 ± 4 m for shallow dives. Respective dive durations (120 ± 18 s and 116 ± 43 s) did not differ. Deep dives resulted in lower minimum SpO2 (58 ± 17%) compared with shallow dives (74 ± 17%; P = 0.029). Overall diving HR was 7 bpm higher in deep dives (P = 0.002) although minimum HR was similar in both types of dives (39 bpm). Three divers desaturated early at depth, of which two exhibited severe hypoxia (SpO2 ≤ 65%) upon resurfacing. Additionally, four divers developed severe hypoxia after dives. CONCLUSIONS Despite similar dive durations, oxygen desaturation was greater during deep dives, confirming increased risk of hypoxic blackout with increased depth. In addition to the rapid drop in alveolar pressure and oxygen uptake during ascent, several other risk factors associated with deep freediving were identified, including higher swimming effort and oxygen consumption, a compromised diving response, an autonomic conflict possibly causing arrhythmias, and compromised oxygen uptake at depth by lung compression possibly leading to atelectasis or pulmonary edema in some individuals. Individuals with elevated risk could likely be identified using wearable technology.
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Affiliation(s)
- Eric Mulder
- Environmental Physiology Group, Department of Health Sciences, Mid Sweden University, Kunskapens Väg 8, 831 25, Östersund, Sweden.
| | - Craig Staunton
- Swedish Winter Sports Research Centre, Mid Sweden University, Östersund, Sweden
| | - Arne Sieber
- Environmental Physiology Group, Department of Health Sciences, Mid Sweden University, Kunskapens Väg 8, 831 25, Östersund, Sweden
- Oxygen Scientific GmbH, Graz, Austria
| | - Erika Schagatay
- Environmental Physiology Group, Department of Health Sciences, Mid Sweden University, Kunskapens Väg 8, 831 25, Östersund, Sweden
- Swedish Winter Sports Research Centre, Mid Sweden University, Östersund, Sweden
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10
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Cansler R, Heidrich J, Whiting A, Tran D, Hall P, Tyler WJ. Influence of CrossFit and Deep End Fitness training on mental health and coping in athletes. Front Sports Act Living 2023; 5:1061492. [PMID: 37849685 PMCID: PMC10577405 DOI: 10.3389/fspor.2023.1061492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 09/19/2023] [Indexed: 10/19/2023] Open
Abstract
Physical exercise is known to improve mental health. Athletes can experience unique physical and emotional stressors, which can deteriorate mental health and cognitive function. Training apathy can lead to cognitive dissonance and further degrade performance by promoting maladaptive, avoidance coping strategies. Introduction of psychosocial and training variables, such as those used in CrossFit (CF) and other community-based fitness programs with strong peer support have been shown to help reduce training apathy and negative affect. Here, we explored whether addition of psychophysiological variation, experienced as "hunger for air" during underwater breath-hold exercises, could provide unique mental health benefits for athletes. We studied the influence of CF and Deep End Fitness (DEF), a community-based underwater fitness program, on several outcome measures of mental health and emotional well-being in volunteer athletes. We observed a significant reduction in stress scores of both the control CF training group and the experimental DEF group. We found that DEF produced a significant improvement in positive affect while CF training did not. Further supportive of our hypothesis that the psychological and biological stressors experienced in underwater, breath-hold training cause positive adaptive changes and benefits, DEF training uniquely increased problem-based coping. While our observations demonstrate both CF and DEF training can improve mental health in athletes, DEF produced additional, unique benefits to positive coping and attitudes of athletes. Future studies should further evaluate the broader benefits of community-based, underwater training programs on psychological and physiological health in athletes and the public.
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Affiliation(s)
- Rachel Cansler
- Department of Psychology, New York University, New York, NY, United States
- Deep End Fitness, San Diego, CA, United States
| | | | - Ali Whiting
- Deep End Fitness, San Diego, CA, United States
| | - Don Tran
- Deep End Fitness, San Diego, CA, United States
| | - Prime Hall
- Deep End Fitness, San Diego, CA, United States
| | - William J. Tyler
- Deep End Fitness, San Diego, CA, United States
- IST, LLC, Birmingham, AL, United States
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11
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Abstract
Pulmonary physiology is significantly altered during underwater exposure, as immersion of the body and increased ambient pressure elicit profound effects on both the cardiovascular and respiratory systems. Thoracic blood pooling, increased breathing gas pressures, and variations in gas volumes alongside ambient pressure changes put the heart and lungs under stress. Normal physiologic function and fitness of the cardiovascular and respiratory systems are prerequisites to safely cope with the challenges of the underwater environment when freediving, or diving with underwater breathing apparatus. Few physicians are trained to understand the physiology and medicine of diving and how to recognize or manage diving injuries. This article provides an overview of the physiologic challenges to the respiratory system during diving, with or without breathing apparatus, and outlines possible health risks and hazards unique to the underwater environment. The underlying pathologic mechanisms of dive-related injuries are reviewed, with an emphasis on pulmonary physiology and pathophysiology.
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Affiliation(s)
- Kay Tetzlaff
- Department of Sports Medicine, University Hospital of Tuebingen, Tuebingen, Germany
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12
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Ibrahim F, Schumacher J, Schwandt L, Herzberg PY. The first shot counts the most: Tactical breathing as an intervention to increase marksmanship accuracy in student officers. MILITARY PSYCHOLOGY 2023:1-12. [PMID: 37733483 DOI: 10.1080/08995605.2023.2258737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 04/07/2023] [Indexed: 09/23/2023]
Abstract
In this study, we investigated the effect of tactical breathing (breath-based stress management) on marksmanship performance in a randomized between-subjects design. The total of n = 100 participants (18% female) were all student soldiers and randomly assigned to the intervention group (tactical breathing) or the control group. In the German Armed Forces shooting simulator, participants shot ten rounds at ten meters with the P8 (Heckler and Koch). In addition, the effect of neuroticism, fear of failure, and resilience on shooting performance and the interaction of those traits with the experimental condition were examined. Overall, the total hit score showed a strong ceiling effect, so the more difficult initial hit was primarily used as a performance criterion. None of the personality traits significantly affected the initial hit, and there were no interactions between the experimental condition and the personality traits. However, there was a significant difference in initial hit between the control and experimental group, as the tactical breathing group shot an average of 1.9 points better, t(98) = 8.489, p < .001, d = 1.698. Considering the initial shot, which was more difficult due to the uncocked trigger, tactical breathing proved to be an effective method for increasing marksmanship performance.
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Affiliation(s)
- Fabio Ibrahim
- Personality Psychology and Psychological Assessment, Helmut-Schmidt-Universität / Universität der Bundeswehr Hamburg: Helmut-Schmidt-Universitat Universitat der Bundeswehr Hamburg, Hamburg, Germany
| | - Jonas Schumacher
- Helmut-Schmidt-Universität / Universität der Bundeswehr Hamburg: Helmut-Schmidt-Universitat Universitat der Bundeswehr Hamburg, Hamburg, Germany
| | - Lars Schwandt
- Helmut-Schmidt-Universität / Universität der Bundeswehr Hamburg: Helmut-Schmidt-Universitat Universitat der Bundeswehr Hamburg, Hamburg, Germany
| | - Philipp Yorck Herzberg
- Helmut-Schmidt-Universität / Universität der Bundeswehr Hamburg: Helmut-Schmidt-Universitat Universitat der Bundeswehr Hamburg, Hamburg, Germany
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13
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Attah AT, Negrón-Moreno PN, Amigo-Duran M, Zhang L, Kenngott M, Brecht M, Clemens AM. Rat Wetness Response: Sensory Cues, Behavior & Fur-based Drying. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.13.557175. [PMID: 37745619 PMCID: PMC10515844 DOI: 10.1101/2023.09.13.557175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
It never rains in standard lab-confinements; thus we have limited understanding of animal reactions to water and wetness. To address this issue, we sprayed water on different body parts of rats and measured drying and fur temperature by thermal imaging while manipulating behavior, sensory cues and fur. Spraying water on rats resulted in fur changes (hair clumping, apex formation), grooming, shaking, and scratching. Anesthesia abolished behavioral responses, interfered with fur changes, and slowed drying. Spraying water on different body parts resulted in differential behavioral drying responses. Spraying the head resulted in grooming and shaking responses; water evaporated twice as fast as water sprayed on the animal's back or belly. We observed no effect of whisker removal on post-water-spraying behavior. In contrast, local anesthesia of dorsal facial skin reduced post-water-spraying behavioral responses. Shaving of head fur drastically enhanced post-water-spraying behaviors, but reduced water loss during drying; indicating that fur promotes evaporation, acting in tandem with behavior to mediate drying. Excised wet fur patches dried and cooled faster than shaved excised wet skin. Water was sucked into distal hair tips, where it evaporated. We propose the wet-fur-heat-pump-hypothesis; fur might extract heat required for drying by cooling ambient air.
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Affiliation(s)
- Augustine Triumph Attah
- Neural Systems & Behavior, Marine Biological Laboratory, 7 MBL Street, Woods Hole, MA 02543 USA
- Washington State University, Pullman, USA
| | - Paola N Negrón-Moreno
- Neural Systems & Behavior, Marine Biological Laboratory, 7 MBL Street, Woods Hole, MA 02543 USA
- Yale University, New Haven, Connecticut, USA
| | - Macarena Amigo-Duran
- Neural Systems & Behavior, Marine Biological Laboratory, 7 MBL Street, Woods Hole, MA 02543 USA
- Biomedicine Research Institute of Buenos Aires - CONICET - Partner Institute of the Max Planck Society (IBioBA-MPSP), Argentina
| | - Linghua Zhang
- Neural Systems & Behavior, Marine Biological Laboratory, 7 MBL Street, Woods Hole, MA 02543 USA
- Krieger Mind/Brain Institute, Johns Hopkins University, Baltimore, USA
| | - Max Kenngott
- Neural Systems & Behavior, Marine Biological Laboratory, 7 MBL Street, Woods Hole, MA 02543 USA
- Brandeis University, Boston, USA
| | - Michael Brecht
- Neural Systems & Behavior, Marine Biological Laboratory, 7 MBL Street, Woods Hole, MA 02543 USA
- Bernstein Center for Computational Neuroscience, Humboldt University of Berlin, Philippstr. 13 Haus 6, 10115 Berlin, Germany
| | - Ann M Clemens
- Neural Systems & Behavior, Marine Biological Laboratory, 7 MBL Street, Woods Hole, MA 02543 USA
- University of Edinburgh, Simons Initiative for the Developing Brain, 1 George Square, EH8 9JZ, Edinburgh, Scotland, United Kingdom
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14
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Prodel E, Cavalvanti T, Divino B, Rocha HNM, Nobrega ACL. Sympathetic control of the coronary circulation during trigeminal nerve stimulation in humans. Eur J Appl Physiol 2023; 123:2063-2071. [PMID: 37179503 DOI: 10.1007/s00421-023-05208-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 04/19/2023] [Indexed: 05/15/2023]
Abstract
PURPOSE We sought to investigate the sympathetic mechanism controlling coronary circulation during trigeminal nerve stimulation in healthy women. METHODS The protocol consisted of 3 min of trigeminal nerve stimulation (TGS) with cold stimuli to the face, in two conditions: (1) control and β-blockade (oral propranolol), and (2) control and α-blockade (oral prazosin). RESULTS Thirty-one healthy young subjects (women: n = 13; men: n = 18) participated in the study. By design, TGS decreased heart rate (HR), and increased blood pressure (BP) and cardiac output (CO). Before the β-blockade coronary blood velocity (CBV-Δ1.4 ± 1.3 cm s-1) increased along with the decrease of coronary vascular conductance index (CVCi-Δ-0.04 ± 0.04 cm s-1 mmHg-1) during TGS and the β-blockade abolished the CBV increase and a further decrease of CVCi was observed with TGS (Δ-0.06 ± 0.07 cm s-1 mmHg-1). During the α-blockade condition before the blockade, the CBV increased (Δ0.93 ± 1.48 cm s-1) along with the decrease of CVCi (Δ-0.05 ± 1.12 cm s-1 mmHg-1) during TGS, after the α-blockade CBV (Δ0.98 ± cm s-1) and CVCi (Δ-0.03 ± 0.06 cm s-1 mmHg-1) response to TGS did not change. CONCLUSION Coronary circulation increases during sympathetic stimulation even with a decrease in heart rate.
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Affiliation(s)
- Eliza Prodel
- Laboratory of Exercise Science, Department of Physiology and Pharmacology, Fluminense Federal University, Alameda Barros Terra S/N, Niteroi, Rio de Janeiro, Brazil.
- National Institute for Science & Technology-INCT (In)Activity & Exercise, Rio de Janeiro, Brazil.
| | - Thiago Cavalvanti
- Laboratory of Exercise Science, Department of Physiology and Pharmacology, Fluminense Federal University, Alameda Barros Terra S/N, Niteroi, Rio de Janeiro, Brazil
- National Institute for Science & Technology-INCT (In)Activity & Exercise, Rio de Janeiro, Brazil
| | - Beatriz Divino
- Laboratory of Exercise Science, Department of Physiology and Pharmacology, Fluminense Federal University, Alameda Barros Terra S/N, Niteroi, Rio de Janeiro, Brazil
- National Institute for Science & Technology-INCT (In)Activity & Exercise, Rio de Janeiro, Brazil
| | - Helena N M Rocha
- Laboratory of Exercise Science, Department of Physiology and Pharmacology, Fluminense Federal University, Alameda Barros Terra S/N, Niteroi, Rio de Janeiro, Brazil
- National Institute for Science & Technology-INCT (In)Activity & Exercise, Rio de Janeiro, Brazil
| | - Antonio C L Nobrega
- Laboratory of Exercise Science, Department of Physiology and Pharmacology, Fluminense Federal University, Alameda Barros Terra S/N, Niteroi, Rio de Janeiro, Brazil
- National Institute for Science & Technology-INCT (In)Activity & Exercise, Rio de Janeiro, Brazil
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15
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Mišić NŽ, Ostojić M, Cvetković S, Miodragović P, Aničić Z, Kovačić Popović A, Stefanović Đ. Wavelet Analysis of Respiratory Muscle sEMG Signals during the Physiological Breakpoint of Static Dry End-Expiratory Breath-Holding in Naive Apneists: A Pilot Study. SENSORS (BASEL, SWITZERLAND) 2023; 23:7200. [PMID: 37631736 PMCID: PMC10459781 DOI: 10.3390/s23167200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 07/18/2023] [Accepted: 07/21/2023] [Indexed: 08/27/2023]
Abstract
The wavelet spectral characteristics of three respiratory muscle signals (scalenus (SC), parasternal intercostal (IC), and rectus abdominis (RA)) and one locomotor muscle (brachioradialis (BR)) were analyzed in the time-frequency (T-F) domain during voluntary breath-holding (BH), with a focus on the physiological breakpoint that is commonly considered the first involuntary breathing movement (IBM) that signals the end of the easy-going phase of BH. The study was performed for an end-expiratory BH physiological breaking point maneuver on twelve healthy, physically active, naive breath-holders/apneists (six professional athletes; six recreational athletes, and two individuals in the post-COVID-19 period) using surface electromyography (sEMG). We observed individual effects that were dependent on muscle oxygenation and each person's fitness, which were consistent with the mechanism of motor unit (MU) recruitment and the transition of slow-twitch oxidative (type 1) to fast-twitch glycolytic (type 2) muscle fibers. Professional athletes had longer BH durations (BHDs) and strong hypercapnic responses regarding the expiratory RA muscle, which is activated abruptly at higher BHDs in a person-specific range below 250 Hz and is dependent on the BHD. This is in contrast with recreational athletes, who had strong hypoxic responses regarding inspiratory IC muscle, which is activated faster and gradually in the frequency range of 250-450 Hz (independent of the person and BHD). This pilot study preliminarily indicates that it is possible to noninvasively assess the physiological characteristics of skeletal muscles, especially oxygenation, and improve physical fitness tests by determining the T-F features of elevated myoelectric IC and RA activity during BH.
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Affiliation(s)
- Nataša Ž. Mišić
- Division of Computational Bioengineering, Research & Development Institute Lola Ltd., 11030 Belgrade, Serbia; (M.O.); (S.C.)
| | - Mirko Ostojić
- Division of Computational Bioengineering, Research & Development Institute Lola Ltd., 11030 Belgrade, Serbia; (M.O.); (S.C.)
| | - Saša Cvetković
- Division of Computational Bioengineering, Research & Development Institute Lola Ltd., 11030 Belgrade, Serbia; (M.O.); (S.C.)
| | - Petar Miodragović
- Department of Physiology, Faculty of Medicine, University of Novi Sad, 21137 Novi Sad, Serbia;
| | - Zdravko Aničić
- Laboratory of Methodology and Research, Faculty of Sport and Physical Education, University of Belgrade, 11030 Belgrade, Serbia;
| | - Anita Kovačić Popović
- Department of Defectology and Clinical Psychology, Medika College for Vocational Studies in Healthcare, 11000 Belgrade, Serbia;
| | - Đorđe Stefanović
- Department for Basic Sports, Faculty of Sport and Physical Education, University of Belgrade, 11030 Belgrade, Serbia;
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16
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Poe E, Bosley R, Steele R, Chesnut C. Trigeminocardiac Reflex: A Review and Key Implications to Dermatologic Surgery. Dermatol Surg 2023; 49:654-658. [PMID: 37134251 DOI: 10.1097/dss.0000000000003808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
BACKGROUND The trigeminocardiac reflex is a common but underreported occurrence that can vary from benign to life threatening. This reflex can be elicited by placing direct pressure on the globe of the eye or from traction of the extraocular muscles, stimulating the trigeminal nerve. OBJECTIVE To provide a review of potential stimuli for the trigeminocardiac reflex within dermatologic surgery and to discuss management options for the treatment of the trigeminocardiac reflex. METHODS PubMed and Cochrane were used to identify articles and case reports that established scenarios in which the trigeminocardiac reflex was provoked and subsequently how the reflex was managed. RESULTS Within the field of dermatologic surgery, the trigeminocardiac reflex can be stimulated during biopsies, cryoablations, injections, laser treatments, Mohs micrographic surgery, and oculoplastic interventions, most often occurring in an office setting. The most common presentations include significant bradycardia, hypotension, gastric hypermobility, and lightheadedness. The most definitive treatment is cessation of the inciting stimulus, monitoring, and symptomatic management. Glycopyrrolate and atropine are common treatments for severe, intractable cases of the trigeminocardiac reflex. CONCLUSION The trigeminocardiac reflex, while underreported and underrepresented in dermatologic literature and dermatologic surgery settings, should be considered in the setting of bradycardia and hypotension during dermatologic procedures.
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Affiliation(s)
- Emily Poe
- Washington State University College of Medicine, Spokane, Washington
| | - Rawn Bosley
- Chesnut MD Cosmetic Surgery Fellowship, Spokane, Washington
| | - Robert Steele
- Chesnut MD Cosmetic Surgery Fellowship, Spokane, Washington
| | - Cameron Chesnut
- University of Washington School of Medicine, Seattle, Washington
- Chesnut MD Cosmetic Surgery Fellowship, Spokane, Washington
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17
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Malinowski KS, Wierzba TH, Neary JP, Winklewski PJ, Wszędybył-Winklewska M. Resting Heart Rate Affects Heart Response to Cold-Water Face Immersion Associated with Apnea. BIOLOGY 2023; 12:869. [PMID: 37372152 DOI: 10.3390/biology12060869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 06/13/2023] [Accepted: 06/14/2023] [Indexed: 06/29/2023]
Abstract
The regular cardiac response to immersion of the face in cold water is reduction in heart rate (HR). The highly individualized and unpredictable course of the cardiodepressive response prompted us to investigate the relationship between the cardiac response to face immersion and the resting HR. The research was conducted with 65 healthy volunteers (37 women and 28 men) with an average age of 21.13 years (20-27 years) and a BMI of 21.49 kg/m2 (16.60-28.98). The face-immersion test consisted of stopping breathing after maximum inhaling and voluntarily immersing the face in cold water (8-10 °C) for as long as possible. Measurements included determination of minimum, average, and maximum HR at rest and minimum and maximum HR during the cold-water face-immersion test. The results indicate a strong relationship between the cardiodepressive reaction of the immersion of the face and the minimum HR before the test, as well as a relationship between the maximum HR during the test and the maximum HR at rest. The results also indicate a strong influence of neurogenic HR regulation on the described relationships. The parameters of the basal HR can, therefore, be used as prognostic indicators of the course of the cardiac response of the immersion test.
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Affiliation(s)
- Krzysztof S Malinowski
- Department of Neurophysiology, Neuropsychology and Neuroinformatics, Faculty of Health Sciences, Medical University of Gdansk, 80-210 Gdansk, Poland
| | - Tomasz H Wierzba
- Department of Physiology, Faculty of Medicine, Medical University of Gdansk, 80-210 Gdansk, Poland
| | - J Patrick Neary
- Faculty of Kinesiology & Health Studies, University of Regina, Regina, SK S4S 0A2, Canada
| | - Paweł J Winklewski
- Department of Neurophysiology, Neuropsychology and Neuroinformatics, Faculty of Health Sciences, Medical University of Gdansk, 80-210 Gdansk, Poland
| | - Magdalena Wszędybył-Winklewska
- Department of Neurophysiology, Neuropsychology and Neuroinformatics, Faculty of Health Sciences, Medical University of Gdansk, 80-210 Gdansk, Poland
- Institute of Health Sciences, Pomeranian University of Slupsk, 76-200 Slupsk, Poland
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18
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Abstract
AbstractThe idea of putting astronauts into a hibernation-like state during interplanetary spaceflights has sparked new interest in the evolutionary roots of hibernation and torpor. In this context, it should be noted that mammalian fetuses and neonates respond to the environmental challenges in the perinatal period with a number of physiological mechanisms that bear striking similarity to hibernation and torpor. These include three main points: first, prenatal deviation from the overall metabolic size relationship, which adapts the fetus to the low-oxygen conditions in the womb and corresponds to the metabolic reduction during hibernation and estivation; second, intranatal diving bradycardia in response to shortened O2 supply during birth, comparable to the decrease in heart rate preceding the drop in body temperature upon entry into torpor; and third, postnatal onset of nonshivering thermogenesis in the brown adipose tissue, along with the increase in basal metabolic rate up to the level expected from body size, such as during arousal from hibernation. The appearance of hibernation-like adaptations in the perinatal period suggests that, conversely, hibernation and torpor may be composed of mechanisms shared by all mammals around birth. This hypothesis sheds new light on the origins of hibernation and supports its potential accessibility to nonhibernating species, including humans.
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19
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Berthelsen LF, Douglas AJM, Dawkins TG, Curry BA, Philips D, Zaidi A, Yousef Z, Stembridge M, Steinback CD. The influence of training status and parasympathetic blockade on the cardiac rate, rhythm, and functional response to autonomic stress. Appl Physiol Nutr Metab 2023; 48:270-282. [PMID: 36634321 DOI: 10.1139/apnm-2022-0340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Apnea (breath-holding) elicits co-activation of sympathetic and parasympathetic nervous systems, affecting cardiac control. In situations of autonomic co-activation (e.g., cold water immersion), cardiac arrhythmias are observed during apnea. Chronic endurance training reduces resting heart rate in part via elevation in parasympathetic tone, and has been identified as a risk factor for development of arrhythmias. However, few studies have investigated autonomic control of the heart in trained athletes during stress. Therefore, we determined whether heightened vagal tone resulting from endurance training promotes a higher incidence of arrhythmia during apnea. We assessed the heart rate, rhythm (ECG lead II), and cardiac inotropic (speckle-tracking echocardiography) response to apnea in 10 endurance trained and 7 untrained participants. Participants performed an apnea at rest and following sympathetic activation using post-exercise circulatory occlusion (PECO). All apneas were performed prior to control (CON) and following vagal block using glycopyrrolate (GLY). Trained participants had lower heart rates at rest (p = 0.03) and during apneas (p = 0.009) under CON. At rest, 3 trained participants exhibited instances of junctional rhythm and 4 trained participants developed ectopy during CON apneas, whereas 3 untrained participants developed ectopic beats only with concurrent sympathetic activation (PECO). Following GLY, no arrhythmias were noted in either group. Vagal block also revealed increased cardiac chronotropy (heart rate) and inotropy (strain rate) during apnea, demonstrating a greater sympathetic influence in the absence of parasympathetic drive. Our results highlight that endurance athletes may be more susceptible to ectopy via elevated vagal tone, whereas untrained participants may only develop ectopy through autonomic conflict.
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Affiliation(s)
- Lindsey F Berthelsen
- Neurovascular Health Lab, Faculty of Kinesiology, Sport and Recreation, University of Alberta, Canada
| | - Andrew J M Douglas
- Cardiff School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, United Kingdom
| | - Tony G Dawkins
- Cardiff School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, United Kingdom.,Centre for Lung and Cardiovascular Health, The University of British Columbia Okanagan, Kelowna, Canada
| | - Bryony A Curry
- Cardiff School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, United Kingdom.,Centre for Lung and Cardiovascular Health, The University of British Columbia Okanagan, Kelowna, Canada
| | - Daniel Philips
- Department of Cardiology, University Hospital of Wales, Cardiff, United Kingdom
| | - Abbas Zaidi
- Department of Cardiology, University Hospital of Wales, Cardiff, United Kingdom
| | - Zaheer Yousef
- Department of Cardiology, University Hospital of Wales, Cardiff, United Kingdom
| | - Mike Stembridge
- Cardiff School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, United Kingdom
| | - Craig D Steinback
- Neurovascular Health Lab, Faculty of Kinesiology, Sport and Recreation, University of Alberta, Canada
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20
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Malinowski KS, Wierzba TH, Neary JP, Winklewski PJ, Wszędybył-Winklewska M. Heart Rate Variability at Rest Predicts Heart Response to Simulated Diving. BIOLOGY 2023; 12:biology12010125. [PMID: 36671817 PMCID: PMC9856132 DOI: 10.3390/biology12010125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 01/09/2023] [Accepted: 01/11/2023] [Indexed: 01/15/2023]
Abstract
A characteristic feature of the cardiac response to diving is the uncertainty in predicting individual course. The aim of the study was to determine whether resting regulatory heart rate determinants assessed before diving may be predictors of cardiac response in a simulated diving test. The research was conducted with 65 healthy volunteers (37 women and 28 men) with an average age of 21.13 years (20-27 years) and a BMI of 21.49 kg/m2 (16.60-28.98). The simulated diving test consisted of stopping breathing after maximum inhaling and voluntarily immersing the face in water (8-10 °C) for as long as possible. The measurements included heart rate variability (HRV) analysis before diving and determination of the course of the cardiac response to diving-minimum and maximum heart rate (HR). The results indicate that minimum HR during diving (MIN_div) is dependent on the short-term HRV measures, which proves the strong influence of the parasympathetic system on the MIN_div. The lack of dependence of MIN_div on short-term HRV in women may be associated with differences in neurogenic HR regulation in women and men. In conclusion, cardiac response to simulated diving is strictly dependent on the autonomic regulation of the heart rhythm under resting conditions. The course of the cardiac response to diving and its relationship with resting HRV appears to be gender dependent.
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Affiliation(s)
- Krzysztof S. Malinowski
- Department of Physiology, Faculty of Medicine, Medical University of Gdansk, 80-210 Gdansk, Poland
- Correspondence: ; Tel.: +48-58-349-15-20
| | - Tomasz H. Wierzba
- Department of Physiology, Faculty of Medicine, Medical University of Gdansk, 80-210 Gdansk, Poland
| | - J. Patrick Neary
- Faculty of Kinesiology & Health Studies, University of Regina, Regina, SK S4S 0A2, Canada
| | - Paweł J. Winklewski
- Department of Human Physiology, Faculty of Health Sciences, Medical University of Gdansk, 80-210 Gdansk, Poland
- Institute of Health Sciences, Pomeranian University of Slupsk, 76-200 Slupsk, Poland
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21
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Burley MJ, Blackwell J, Bond B, Williams C, Stephens FB. The effect of various breath-hold techniques on the cardiorespiratory response to facial immersion in humans. Exp Physiol 2023; 108:50-62. [PMID: 36448400 PMCID: PMC10103768 DOI: 10.1113/ep090531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 11/07/2022] [Indexed: 12/03/2022]
Abstract
NEW FINDINGS What is the central question of this study? What is the effect of three repeated breath-hold techniques routinely used by freedivers, thought to manipulate arterial partial pressures of O2 and CO2 , on the cardiorespiratory and haematological response to breath-holding during facial immersion? What is the main finding and its importance? All three techniques increased breath-hold by a similar duration, probably owing to the similar marked increase in end-tidal O2 and decrease in end-tidal CO2 observed in all three trials before facial immersion. These were the only cardiorespiratory changes that were consistently manipulated before the maximal breath-hold. This would suggest that pronounced bradycardia and vasoconstriction of selective vascular beds are probably not obligatory for prolonging breath-hold duration. ABSTRACT Repeated maximal breath-holds have been demonstrated to induce bradycardia, increase haematocrit and haemoglobin and prolong subsequent breath-hold duration by 20%. Freedivers use non-maximal breath-hold techniques (BHTs) to improve breath-hold duration. The aim of this study was to investigate the cardiorespiratory and haematological responses to various BHTs. Ten healthy men (34.5 ± 1.9 years) attended five randomized experimental trials and performed a 40 min period of quiet rest or one of three BHTs followed by a maximal breath-hold challenge during facial immersion in water at 30 or 10°C. Cardiovascular and respiratory parameters were measured continuously using finger plethysmography and breath-by-breath gas analysis, respectively, and venous blood samples were collected throughout. Facial immersion in cold water caused marked bradycardia (74.1 vs. 50.2 beats/min after 40 s) but did not increase breath-hold duration compared with warm water control conditions. Facial immersion breath-hold duration was 30.8-43.3% greater than the control duration when preceded by BHTs that involved repeated breath-holds of constant duration (P = 0.021), increasing duration (P < 0.001) or increasing frequency (P < 0.001), with no difference observed between BHTs. The increased duration of apnoea across all three BHT protocols was associated with a 6.8% increase in end-tidal O2 and a 13.1% decrease in end-tidal CO2 immediately before facial immersion. There were no differences in blood pressure, cardiac output, heart rate, haematocrit or haemoglobin between each BHT and control conditions (P > 0.05). In conclusion, the duration of apnoea can be extended by manipulating blood gases through repeated prior breath-holds, but changes in cardiac output and red blood cell mass do not appear essential.
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Affiliation(s)
- Matthew J. Burley
- Department of Sport and Health SciencesCollege of Life and Environmental SciencesUniversity of ExeterExeterUK
| | - Jamie Blackwell
- Department of Sport and Health SciencesCollege of Life and Environmental SciencesUniversity of ExeterExeterUK
| | - Bert Bond
- Department of Sport and Health SciencesCollege of Life and Environmental SciencesUniversity of ExeterExeterUK
| | - Craig Williams
- Department of Sport and Health SciencesCollege of Life and Environmental SciencesUniversity of ExeterExeterUK
| | - Francis B. Stephens
- Department of Sport and Health SciencesCollege of Life and Environmental SciencesUniversity of ExeterExeterUK
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22
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Persson G, Lodin-Sundström A, Linér MH, Andersson SHA, Sjögreen B, Andersson JPA. Splenic contraction and cardiovascular responses are augmented during apnea compared to rebreathing in humans. Front Physiol 2023; 14:1109958. [PMID: 36960158 PMCID: PMC10028099 DOI: 10.3389/fphys.2023.1109958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 02/22/2023] [Indexed: 03/09/2023] Open
Abstract
The spleen contracts during apnea, releasing stored erythrocytes, thereby increasing systemic hemoglobin concentration (Hb). We compared apnea and rebreathing periods, of equal sub-maximal duration (mean 137 s; SD 30), in eighteen subjects to evaluate whether respiratory arrest or hypoxic and hypercapnic chemoreceptor stimulation is the primary elicitor of splenic contraction and cardiovascular responses during apnea. Spleen volume, Hb, cardiovascular variables, arterial (SaO2), cerebral (ScO2), and deltoid muscle oxygen saturations (SmO2) were recorded during the trials and end-tidal partial pressure of oxygen (PETO2) and carbon dioxide (PETCO2) were measured before and after maneuvers. The spleen volume was smaller after apnea, 213 (89) mL, than after rebreathing, 239 (95) mL, corresponding to relative reductions from control by 20.8 (17.8) % and 11.6 (8.0) %, respectively. The Hb increased 2.4 (2.0) % during apnea, while there was no significant change with rebreathing. The cardiovascular responses, including bradycardia, decrease in cardiac output, and increase in total peripheral resistance, were augmented during apnea compared to during rebreathing. The PETO2 was higher, and the PETCO2 was lower, after apnea compared to after rebreathing. The ScO2 was maintained during maneuvers. The SaO2 decreased 3.8 (3.1) % during apnea, and even more, 5.4 (4.4) %, during rebreathing, while the SmO2 decreased less during rebreathing, 2.2 (2.8) %, than during apnea, 8.3 (6.2) %. We conclude that respiratory arrest per se is an important stimulus for splenic contraction and Hb increase during apnea, as well as an important initiating factor for the apnea-associated cardiovascular responses and their oxygen-conserving effects.
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Affiliation(s)
- Gustav Persson
- Department of Experimental Medical Science, Lund University, Lund, Sweden
- *Correspondence: Gustav Persson, ; Johan P. A. Andersson,
| | - Angelica Lodin-Sundström
- Department of Health Sciences, Mid Sweden University, Sundsvall, Sweden
- Department of Biology, Lund University, Lund, Sweden
| | - Mats H. Linér
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Samuel H. A. Andersson
- Department of Biology, Lund University, Lund, Sweden
- Department of Clinical Sciences, Malmö, Lund University, Lund, Sweden
| | | | - Johan P. A. Andersson
- Department of Experimental Medical Science, Lund University, Lund, Sweden
- *Correspondence: Gustav Persson, ; Johan P. A. Andersson,
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23
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Carotid body stimulation as a potential intervention in sudden death in epilepsy. Epilepsy Behav 2022; 136:108918. [PMID: 36202052 PMCID: PMC10187768 DOI: 10.1016/j.yebeh.2022.108918] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Revised: 09/09/2022] [Accepted: 09/11/2022] [Indexed: 12/14/2022]
Abstract
OBJECTIVE To investigate carotid body (CB) mechanisms related to sudden death during seizure. Ictal activation of oxygen-conserving reflexes (OCRs) can trigger fatal cardiorespiratory collapse in seizing rats, which presents like human sudden unexpected death in epilepsy (SUDEP). The CB is strongly implicated in OCR pathways; we hypothesize that modulating CB activity will provide insight into these mechanisms of death. METHODS Long-Evans rats were anesthetized with urethane. Recordings included: electrocorticography, electrocardiography, respiration via nasal thermocouple, and blood pressure (BP). The mammalian diving reflex (MDR) was activated by cold water delivered through a nasal cannula. Reflex and stimulation trials were repeated up to 16 times (4 pre-intervention, 12 post-intervention) or until death. In some animals, one or both carotid bodies were denervated. In some animals, the CB was electrically stimulated, both with and without MDR. Seizures were induced with kainic acid (KA). RESULTS Animals without seizure and with no CB modulation survived all reflexes. Non-seizing animals with CB denervation survived 7.1 ± 5.4 reflexes before death, and only 1 of 7 survived past the 12-trial threshold. Electrical CB stimulation without seizure and without reflex caused significant tachypnea and hypotension. Electrical CB stimulation with seizure and without reflex required higher amplitudes to replicate the physiological responses seen outside seizure. Seizing animals without CB intervention survived 3.2 ± 3.6 trials (per-reflex survival rate 42.0% ± 44.4%), and 0 of 7 survived past the 12-trial threshold. Seizing animals with electrical CB stimulation survived 10.5 ± 4.7 ictal trials (per-reflex survival rate 86.3% ± 35.0%), and 6 of 8 survived past the 12-trial threshold. SIGNIFICANCE These results suggest that, during seizure, the ability of the CB to stimulate a restart of respiration is impaired. The CB and its afferents may be relevant to fatal ictal apnea and SUDEP in humans, and CB stimulation may be a relevant intervention technique in these deaths.
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24
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Peng H, Oikawa S, Inai Y, Maeda S, Akama T. Effects of lung volume and trigeminal nerve stimulation on diving response in breath-hold divers and non-divers. Respir Physiol Neurobiol 2022; 303:103918. [PMID: 35550439 DOI: 10.1016/j.resp.2022.103918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 04/21/2022] [Accepted: 05/05/2022] [Indexed: 10/18/2022]
Abstract
PURPOSE This study investigated the effects of lung volume and trigeminal nerve stimulation (TS) on diving responses in breath-hold divers (BHDs) and non-divers (NDs). METHODS Eight BHDs and nine NDs performed four breath-hold trials at different lung volumes, with or without TS, and one trial of TS. Haemodynamic parameters and electrocardiograms were measured for each trial. RESULTS During the TS trial, the total peripheral resistance increased more in BHDs. Breath-hold performed at total lung capacity showed a more pronounced decrease in stroke volume and cardiac output in BHDs. The decrease in heart rate and increase in total peripheral resistance were more pronounced in BHDs when breath-holding was performed with TS. CONCLUSION The more pronounced diving response in BHDs was attributed to the greater increase in total peripheral resistance caused by TS. Furthermore, the lower stroke volume and cardiac output in BH performed at total lung capacity could also cause a more pronounced diving response in BHDs.
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Affiliation(s)
- Heng Peng
- Graduate School of Sport Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa-city, Saitama 359-1192, Japan.
| | - Satoshi Oikawa
- Faculty of Sport Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa-city, Saitama 359-1192, Japan
| | - Yuto Inai
- Graduate School of Sport Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa-city, Saitama 359-1192, Japan
| | - Seiji Maeda
- Faculty of Sport Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa-city, Saitama 359-1192, Japan
| | - Takao Akama
- Faculty of Sport Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa-city, Saitama 359-1192, Japan
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25
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Kelly T, Brown C, Bryant-Ekstrand M, Lord R, Dawkins T, Drane A, Futral JE, Barak O, Dragun T, Stembridge M, Spajić B, Drviš I, Duke JW, Ainslie PN, Foster GE, Dujic Z, Lovering AT. Blunted hypoxic pulmonary vasoconstriction in apnoea divers. Exp Physiol 2022; 107:1225-1240. [PMID: 35993480 DOI: 10.1113/ep090326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 08/11/2022] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is new and noteworthy? What is the central question of this study? Does the hyperbaric, hypercapnic, acidotic, hypoxic stress of apnoea diving lead to greater pulmonary vasoreactivity and increased right-heart work in apnoea divers? What is the main finding and its importance? Compared to sex- and age-matched controls, Divers had a significantly lower change in total pulmonary resistance in response to short duration isocapnic hypoxia. With oral sildenafil (50 mg), there were no differences in total pulmonary resistance between groups, suggesting Divers can maintain normal pulmonary artery tone in hypoxic conditions. Blunted hypoxic pulmonary vasoconstriction may be beneficial during apnoea diving. ABSTRACT Competitive apnoea divers repetitively dive to depths beyond 50 m. During the final portions of ascent, Divers experience significant hypoxaemia. Additionally, hyperbaria during diving increases thoracic blood volume while simultaneously reducing lung volume, increasing pulmonary artery pressure. We hypothesized that Divers would have exaggerated hypoxic pulmonary vasoconstriction leading to increased right-heart work due to their repetitive hypoxaemia and hyperbaria, and that the administration of sildenafil would have a greater effect in reducing pulmonary resistance in Divers. We recruited 16 Divers and 16 age and sex matched non-diving controls (Controls). Using a double-blinded, placebo-controlled, cross-over design, participants were evaluated for normal cardiac and lung function, then their cardiopulmonary responses to 20-30 minutes of isocapnic hypoxia (end-tidal PO2 = 50 mm Hg) were measured one hour following ingestion of 50 mg sildenafil or placebo. Cardiac structure and cardiopulmonary function were similar at baseline. With placebo, Divers had a significantly smaller increase in total pulmonary resistance than controls after 20-30 minutes isocapnic hypoxia (Δ -3.85 ± 72.85 vs 73.74 ± 91.06 dynes/sec/cm-5 , p = .0222). With sildenafil, Divers and Controls had similarly blunted increases in total pulmonary resistance after 20-30 minutes of hypoxia. Divers also had a significantly lower systemic vascular resistance following sildenafil in normoxia. These data indicate that repetitive apnoea diving leads to a blunted hypoxic pulmonary vasoconstriction. We suggest this is a beneficial adaption allowing for increased cardiac output with reduced right heart work and thus reducing cardiac oxygen utilization under hypoxemic conditions. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Tyler Kelly
- Department of Human Physiology, University of Oregon, Eugene, Oregon, USA
| | - Courtney Brown
- Centre for Heart, Lung, and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, BC, Canada
| | | | - Rachel Lord
- School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, Wales, UK
| | - Tony Dawkins
- School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, Wales, UK
| | - Aimee Drane
- School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, Wales, UK
| | - Joel E Futral
- Department of Human Physiology, University of Oregon, Eugene, Oregon, USA
| | - Otto Barak
- Department of Physiology, University of Novi Sad, Novi Sad, Serbia
| | - Tanja Dragun
- Department of Integrative Physiology, University of Split School of Medicine, Split, Croatia
| | - Michael Stembridge
- School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, Wales, UK
| | - Boris Spajić
- Faculty of Kinesiology, University of Zagreb, Zagreb, Croatia
| | - Ivan Drviš
- Faculty of Kinesiology, University of Zagreb, Zagreb, Croatia
| | - Joseph W Duke
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, USA
| | - Philip N Ainslie
- Centre for Heart, Lung, and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, BC, Canada
| | - Glen E Foster
- Centre for Heart, Lung, and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, BC, Canada
| | - Zeljko Dujic
- Department of Integrative Physiology, University of Split School of Medicine, Split, Croatia
| | - Andrew T Lovering
- Department of Human Physiology, University of Oregon, Eugene, Oregon, USA
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26
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Williams TM, Blackwell SB, Tervo O, Garde E, Sinding MS, Richter B, Heide‐Jørgensen MP. Physiological responses of narwhals to anthropogenic noise: A case study with seismic airguns and vessel traffic in the Arctic. Funct Ecol 2022. [DOI: 10.1111/1365-2435.14119] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Terrie M. Williams
- Coastal Biology Building‐ Department of Ecology and Evolutionary Biology, 130 McAllister Way University of California‐ Santa Cruz CA
| | | | - Outi Tervo
- Greenland Institute of Natural Resources Copenhagen K Denmark
| | - Eva Garde
- Greenland Institute of Natural Resources Copenhagen K Denmark
| | | | - Beau Richter
- Coastal Biology Building‐ Department of Ecology and Evolutionary Biology, 130 McAllister Way University of California‐ Santa Cruz CA
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27
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Vitali L, Raffi M, Piras A. Acute Cardiovascular and Metabolic Effects of Different Warm-Up Protocols on Dynamic Apnea. J Sports Sci Med 2022; 21:298-307. [PMID: 35719233 PMCID: PMC9157517 DOI: 10.52082/jssm.2022.298] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 05/22/2022] [Indexed: 06/15/2023]
Abstract
The aim of this study was to evaluate the acute physiological response to different warm-up protocols on the dynamic apnea performance. The traditional approach, including a series of short-mid dives in water (WET warm-up), was compared to a more recent strategy, consisting in exercises performed outside the water (DRY warm-up). Nine athletes were tested in two different sessions, in which the only difference was the warm-up executed before 75m of dynamic apnea. Heart rate variability, baroreflex sensitivity, hemoglobin, blood lactate and the rate of perceived exertion were recorded and analyzed. With respect to WET condition, DRY showed lower lactate level before the dive (1.93 vs. 2.60 mmol/L, p = 0.006), higher autonomic indices and lower heart rate during the subsequent dynamic apnea. A significant correlation between lactate produced during WET with the duration of the subsequent dynamic apnea, suggests that higher lactate levels could affect the dive performance (72 vs. 70 sec, p = 0.028). The hemoglobin concentration and the rate of perceived exertion did not show significant differences between conditions. The present findings partially support the claims of freediving athletes who adopt the DRY warm-up, since it induces a more pronounced diving response, avoiding higher lactate levels and reducing the dive time of a dynamic apnea.
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Affiliation(s)
- Luca Vitali
- Department for Life Quality Studies, University of Bologna, Italy
| | - Milena Raffi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy
| | - Alessandro Piras
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy
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28
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Spicher B, Fischer K, Zimmerli ZA, Yamaji K, Ueki Y, Bertschinger CN, Jung B, Otsuka T, Bigler MR, Gräni C, von Tengg-Kobligk H, Räber L, Eberle B, Guensch DP. Combined Analysis of Myocardial Deformation and Oxygenation Detects Inducible Ischemia Unmasked by Breathing Maneuvers in Chronic Coronary Syndrome. Front Cardiovasc Med 2022; 9:800720. [PMID: 35282374 PMCID: PMC8907543 DOI: 10.3389/fcvm.2022.800720] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2021] [Accepted: 01/31/2022] [Indexed: 12/20/2022] Open
Abstract
Introduction In patients with chronic coronary syndromes, hyperventilation followed by apnea has been shown to unmask myocardium susceptible to inducible deoxygenation. The aim of this study was to assess whether such a provoked response is co-localized with myocardial dysfunction. Methods A group of twenty-six CAD patients with a defined stenosis (quantitative coronary angiography > 50%) underwent a cardiovascular magnetic resonance (CMR) exam prior to revascularization. Healthy volunteers older than 50 years served as controls (n = 12). Participants hyperventilated for 60s followed by brief apnea. Oxygenation-sensitive images were analyzed for changes in myocardial oxygenation and strain. Results In healthy subjects, hyperventilation resulted in global myocardial deoxygenation (-10.2 ± 8.2%, p < 0.001) and augmented peak circumferential systolic strain (-3.3 ± 1.6%, p < 0.001). At the end of apnea, myocardial signal intensity had increased (+9.1 ± 5.3%, p < 0.001) and strain had normalized to baseline. CAD patients had a similar global oxygenation response to hyperventilation (−5.8 ± 9.6%, p = 0.085) but showed no change in peak strain from their resting state (-1.3 ± 1.6%), which was significantly attenuated in comparison the strain response observed in controls (p = 0.008). With apnea, the CAD patients showed an attenuated global oxygenation response to apnea compared to controls (+2.7 ± 6.2%, p < 0.001). This was accompanied by a significant depression of peak strain (3.0 ± 1.7%, p < 0.001), which also differed from the control response (p = 0.025). Regional analysis demonstrated that post-stenotic myocardium was most susceptible to de-oxygenation and systolic strain abnormalities during respiratory maneuvers. CMR measures at rest were unable to discriminate post-stenotic territory (p > 0.05), yet this was significant for both myocardial oxygenation [area under the curve (AUC): 0.88, p > 0.001] and peak strain (AUC: 0.73, p = 0.023) measured with apnea. A combined analysis of myocardial oxygenation and peak strain resulted in an incrementally higher AUC of 0.91, p < 0.001 than strain alone. Conclusion In myocardium of patients with chronic coronary syndromes and primarily intermediate coronary stenoses, cine oxygenation-sensitive CMR can identify an impaired vascular and functional response to a vasoactive breathing maneuver stimulus indicative of inducible ischemia.
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Affiliation(s)
- Barbara Spicher
- Department of Anaesthesiology and Pain Medicine, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Kady Fischer
- Department of Anaesthesiology and Pain Medicine, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Zoe A. Zimmerli
- Department of Anaesthesiology and Pain Medicine, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Kyohei Yamaji
- Department of Cardiology, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Yasushi Ueki
- Department of Cardiology, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Carina N. Bertschinger
- Department of Diagnostic, Interventional and Paediatric Radiology, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Bernd Jung
- Department of Diagnostic, Interventional and Paediatric Radiology, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Tatsuhiko Otsuka
- Department of Cardiology, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Marius R. Bigler
- Department of Cardiology, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Christoph Gräni
- Department of Cardiology, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Hendrik von Tengg-Kobligk
- Department of Diagnostic, Interventional and Paediatric Radiology, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Lorenz Räber
- Department of Cardiology, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Balthasar Eberle
- Department of Anaesthesiology and Pain Medicine, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Dominik P. Guensch
- Department of Anaesthesiology and Pain Medicine, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
- Department of Diagnostic, Interventional and Paediatric Radiology, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
- *Correspondence: Dominik P. Guensch
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29
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Guimard A, Joulia F, Prieur F, Poszalczyk G, Helme K, Lhuissier FJ. Exponential Relationship Between Maximal Apnea Duration and Exercise Intensity in Non-apnea Trained Individuals. Front Physiol 2022; 12:815824. [PMID: 35145428 PMCID: PMC8821942 DOI: 10.3389/fphys.2021.815824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 12/22/2021] [Indexed: 11/13/2022] Open
Abstract
It is well known that the duration of apnea is longer in static than in dynamic conditions, but the impact of exercise intensity on the apnea duration needs to be investigated. The aim of this study was to determine the relationship between apnea duration and exercise intensity, and the associated metabolic parameters. Ten healthy active young non-apnea trained (NAT) men participated in this study. During the first visit, they carried out a maximum static apnea (SA) and a maximal progressive cycle exercise to evaluate the power output achieved at peak oxygen uptake (PVO2peak). During the second visit, they performed four randomized dynamic apneas (DAs) at 20, 30, 40, and 50% of PVO2peak (P20, P30, P40, and P50) preceded by 4 min of exercise without apnea. Duration of apnea, heart rate (HR), arterial oxygen saturation (SpO2), blood lactate concentration [La], rating of perceived exertion (RPE), and subjective feeling were recorded. Apnea duration was significantly higher during SA (68.1 ± 23.6 s) compared with DA. Apnea duration at P20 (35.6 ± 11.7 s) was higher compared with P30 (25.6 ± 6.3 s), P40 (19.2 ± 6.7 s), and P50 (16.9 ± 2.5 s). The relationship between apnea duration and exercise intensity followed an exponential function (y = 56.388e-0.025 x ). SA as DA performed at P20 and P30 induces a bradycardia. Apnea induces an SpO2 decrease which is higher during DA (-10%) compared with SA (-4.4%). The decreases of SPO2 recorded during DA do not differ despite the increase in exercise intensity. An increase of [La] was observed in P30 and P40 conditions. RPE and subjective feeling remained unchanged whatever the apnea conditions might be. These results suggest that the DA performed at 30% of VO2peak could be the best compromise between apnea duration and exercise intensity. Then, DA training at low intensity could be added to aerobic training since, despite the moderate hypoxia, it is sufficient to induce and increase [La] generally observed during high-intensity training.
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Affiliation(s)
- Alexandre Guimard
- Université Sorbonne Paris Nord, Hypoxie et Poumon, H&P, INSERM, UMR 1272, Bobigny, France.,Département STAPS, Université Sorbonne Paris Nord, Bobigny, France
| | - Fabrice Joulia
- Center for Cardiovascular and Nutrition Research (C2VN), INSERM 1263, INRAE 1260, Aix Marseille Université, Marseille, France.,UFR STAPS, Toulon, France
| | - Fabrice Prieur
- Université Paris-Saclay, CIAMS, Orsay, France.,Université d'Orléans, CIAMS, Orléans, France
| | - Gauthier Poszalczyk
- Université Sorbonne Paris Nord, Hypoxie et Poumon, H&P, INSERM, UMR 1272, Bobigny, France.,Département STAPS, Université Sorbonne Paris Nord, Bobigny, France
| | - Kader Helme
- Université Sorbonne Paris Nord, Hypoxie et Poumon, H&P, INSERM, UMR 1272, Bobigny, France.,Département STAPS, Université Sorbonne Paris Nord, Bobigny, France
| | - François J Lhuissier
- Université Sorbonne Paris Nord, Hypoxie et Poumon, H&P, INSERM, UMR 1272, Bobigny, France.,Assistance Publique - Hôpitaux de Paris, Hôpitaux Universitaires Paris Seine-Saint-Denis, Hôpital Jean Verdier, Médecine de l'Exercice et du Sport, Bondy, France
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30
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Veiga S, Pla R, Qiu X, Boudet D, Guimard A. Effects of Extended Underwater Sections on the Physiological and Biomechanical Parameters of Competitive Swimmers. Front Physiol 2022; 13:815766. [PMID: 35177993 PMCID: PMC8845443 DOI: 10.3389/fphys.2022.815766] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 01/10/2022] [Indexed: 12/05/2022] Open
Abstract
Despite changes in the underwater sections of swimming races affecting overall performance, there is no information about the effects of the apnea-induced changes on the physiological state of competitive swimmers. The aim of the present research was to examine the effect of changes in the underwater race sections on the physiological [blood lactate concentration, heart rate, and rating of perceived exertion (RPE)] and biomechanical (underwater time, distance, and velocity) parameters of competitive swimmers. Twelve youth competitive swimmers belonging to the national team (706 ± 28.9 FINA points) performed 2 × 75 m efforts under three different conditions, while maintaining a 200 m race pace: (1) free underwater sections, (2) kick number of condition 1 plus two kicks, and (3) maximum distance underwater. Overall performance was maintained, and underwater section durations increased from condition 1 to 3 as expected according to the experimental design. Heart rate and blood lactate concentration values did not show differences between conditions, but the RPE values were significantly greater (F2, 36 = 18.00, p = 0.001, η2: 0.50) for the constrained (conditions 2 and 3) vs. the free underwater condition. Underwater parameters were modified within the 75 m efforts (lap 1 to lap 3), but the magnitude of changes did not depend on the experimental condition (all lap × condition effects p > 0.05). Controlled increases of underwater sections in trained swimmers can led to optimizing performance in these race segments despite small increases of perceived discomfort.
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Affiliation(s)
- Santiago Veiga
- Departamento de Deportes, Facultad de Ciencias de la Actividad Física y del Deporte—INEF, Universidad Politécnica de Madrid, Madrid, Spain
| | - Robin Pla
- French Swimming Federation, Clichy, France
- Institut de Recherche BioMédicale et d’Epidémiologie du Sport, IRMES, Paris, France
| | - Xiao Qiu
- Departamento de Deportes, Facultad de Ciencias de la Actividad Física y del Deporte—INEF, Universidad Politécnica de Madrid, Madrid, Spain
- Institute of Sports and Sport Science, University of Kassel, Kassel, Germany
| | | | - Alexandre Guimard
- Université Sorbonne Paris Nord, Hypoxie et Poumon, H&P, INSERM, UMR 1272, Bobigny, France
- Département STAPS, Université Sorbonne Paris Nord, Bobigny, France
- *Correspondence: Alexandre Guimard,
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Nordine M, Schwarz A, Bruckstein R, Gunga HC, Opatz O. The Human Dive Reflex During Consecutive Apnoeas in Dry and Immersive Environments: Magnitude and Synchronicity. Front Physiol 2022; 12:725361. [PMID: 35058791 PMCID: PMC8764278 DOI: 10.3389/fphys.2021.725361] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 11/23/2021] [Indexed: 11/13/2022] Open
Abstract
Introduction: The human dive reflex (HDR), an O2 conserving reflex, is characterised by an interplay of central parasympathetic and peripheral sympathetic reactions, which are presumed to operate independently of each other. The HDR is fully activated during apnoea with facial immersion in water and complete immersion in water is thought to increase the magnitude of HDR during consecutive apnoeas. A comparison of HDR activity between consecutive apnoeas in full-body immersion with consecutive apnoeas in dry conditions has not been fully explored. Also, the interplay between parasympathetic and sympathetic reactions involved in the HDR has not been thoroughly analysed. Methods: 11 human volunteers performed 3 consecutive 60 s apnoeas with facial immersion in dry conditions (FIDC) and 3 consecutive apnoeas with facial immersion in full immersion (FIFI). Heart rate (HR), R-R interval (RRI), finger pulse amplitude (FPA), splenic width (SW) and SpO2 were all measured before, during and after apnoeas. A one-way ANOVA using Dunn's post hoc test was performed to assess HDR activity, and a Pearson's correlation test was performed to assess HDR synchronisation between physiological parameters during both conditions. Results: Although HDR activity was not significantly different between both conditions, HR and RRI showed progressively greater changes during FIFI compared with FIDC, while SW and FPA changes were relatively equivalent. During FIDC, significant correlations were found between SW & SpO2 and FPA & SpO2. During FIFI, significant correlations were found between RRI & FPA, SW & FPA, HR & SpO2 and FPA & SpO2. Discussion: While there was no significant difference found between HDR activity during FIDC and FIFI, consecutive apnoeas during FIFI triggered a greater magnitude of cardiac activity. Furthermore, significant correlations between RRI and SW with FPA indicate a crosstalk between parasympathetic tone with splenic contraction and increased peripheral sympathetic outflow during FIFI compared to FIDC. In conclusion, HDR activity during consecutive apnoeas does not differ between FIDC and FIFI. There appears to be however a greater level of synchronicity during apnoeas in FIFI compared to FIDC and that this is most likely due to the physiological effects of immersion, which could induce neural recruitment and increased cross talk of HDR pathways.
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Affiliation(s)
- Michael Nordine
- Charité Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Clinic for Anesthesiology, Campus Benjamin Franklin Berlin, Berlin, Germany
| | - Anton Schwarz
- Monash School of Medicine, Monash University, Clayton, VIC, Australia
| | - Renana Bruckstein
- Charité Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Clinic for Anesthesiology, Campus Benjamin Franklin Berlin, Berlin, Germany
| | - Hanns-Christian Gunga
- Charité Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Clinic for Anesthesiology, Campus Benjamin Franklin Berlin, Berlin, Germany
| | - Oliver Opatz
- Charité Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Clinic for Anesthesiology, Campus Benjamin Franklin Berlin, Berlin, Germany
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Fico BG, Alhalimi TA, Tanaka H. Vascular Responses to Simulated Breath-Hold Diving Involving Multiple Reflexes. Am J Physiol Regul Integr Comp Physiol 2022; 322:R153-R160. [PMID: 35018822 DOI: 10.1152/ajpregu.00202.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Breath-hold diving evokes a complex cardiovascular response. The degrees of hypertension induced by the diving reflex are substantial and accentuated by the underwater swimming. This condition provides a circulatory challenge to properly buffer and cushion cardiac pulsations. We determined hemodynamic changes during the diving maneuver. A total of 20 healthy young adults were studied. Hemodynamics were measured during exercise on a cycle ergometer, apnea, face immersion in cold water (trigeminal stimulation), and simulated breath-hold diving. Dynamic arterial compliance (measured by changes in carotid artery diameter via ultrasound divided by changes in carotid blood pressure as assessed by arterial tonometry) increased with simulated diving compared with rest (p=0.007) and was elevated compared with exercise and apnea alone (p<0.01). A significant increase in heart rate was observed with exercise, apnea, and facial immersion when compared with rest (p<0.001). However, simulated diving brought the heart rate down to resting levels. Cardiac output increased with all conditions (p<0.001), with an attenuated response during simulated diving compared with exercise and facial immersion (p<0.05). Mean blood pressure was elevated during all conditions (p<0.001), with a further elevation observed during simulated diving compared with exercise (p<0.001), apnea (p=0.016), and facial immersion (p<0.001). Total peripheral resistance was decreased during exercise and facial immersion compared with rest (p<0.001) but was increased during simulated diving compared with exercise (p<0.001), apnea (p=0.008), and facial immersion (p=0.003). We concluded that central artery compliance is augmented during simulated breath-hold diving to help buffer cardiac pulsations.
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Affiliation(s)
- Brandon G Fico
- Cardiovascular Aging Research Laboratory, Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, TX, United States
| | - Taha Ali Alhalimi
- Cardiovascular Aging Research Laboratory, Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, TX, United States
| | - Hirofumi Tanaka
- Cardiovascular Aging Research Laboratory, Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, TX, United States
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Kjeld T, Isbrand AB, Linnet K, Zerahn B, Højberg J, Hansen EG, Gormsen LC, Bejder J, Krag T, Vissing J, Bøtker HE, Arendrup HC. Extreme Hypoxia Causing Brady-Arrythmias During Apnea in Elite Breath-Hold Divers. Front Physiol 2021; 12:712573. [PMID: 34925050 PMCID: PMC8678416 DOI: 10.3389/fphys.2021.712573] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 09/27/2021] [Indexed: 11/13/2022] Open
Abstract
Introduction: The cardiac electrical conduction system is very sensitive to hypoglycemia and hypoxia, and the consequence may be brady-arrythmias. Weddell seals endure brady-arrythmias during their dives when desaturating to 3.2 kPa and elite breath-hold-divers (BHD), who share metabolic and cardiovascular adaptions including bradycardia with diving mammals, endure similar desaturation during maximum apnea. We hypothesized that hypoxia causes brady-arrythmias during maximum apnea in elite BHD. Hence, this study aimed to define the arterial blood glucose (Glu), peripheral saturation (SAT), heart rhythm (HR), and mean arterial blood pressure (MAP) of elite BHD during maximum apneas. Methods: HR was monitored with Direct-Current-Pads/ECG-lead-II and MAP and Glu from a radial arterial-catheter in nine BHD performing an immersed and head-down maximal static pool apnea after three warm-up apneas. SAT was monitored with a sensor on the neck of the subjects. On a separate day, a 12-lead-ECG-monitored maximum static apnea was repeated dry (n = 6). Results: During pool apnea of maximum duration (385 ± 70 s), SAT decreased from 99.6 ± 0.5 to 58.5 ± 5.5% (∼PaO2 4.8 ± 1.5 kPa, P < 0.001), while Glu increased from 5.8 ± 0.2 to 6.2 ± 0.2 mmol/l (P = 0.009). MAP increased from 103 ± 4 to 155 ± 6 mm Hg (P < 0.005). HR decreased to 46 ± 10 from 86 ± 14 beats/minute (P < 0.001). HR and MAP were unchanged after 3–4 min of apnea. During dry apnea (378 ± 31 s), HR decreased from 55 ± 4 to 40 ± 3 beats/minute (P = 0.031). Atrioventricular dissociation and junctional rhythm were observed both during pool and dry apneas. Conclusion: Our findings contrast with previous studies concluding that Glu decreases during apnea diving. We conclude during maximum apnea in elite BHD that (1) the diving reflex is maximized after 3–4 min, (2) increasing Glu may indicate lactate metabolism in accordance with our previous results, and (3) extreme hypoxia rather than hypoglycemia causes brady-arrythmias in elite BHD similar to diving mammals.
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Affiliation(s)
- Thomas Kjeld
- Department of Anesthesiology, Herlev Hospital, University of Copenhagen, Copenhagen, Denmark
| | - Anders Brenøe Isbrand
- Department of Clinical Physiology and Nuclear Medicine, Herlev Hospital, University of Copenhagen, Copenhagen, Denmark
| | - Katrine Linnet
- Department of Anesthesiology, Herlev Hospital, University of Copenhagen, Copenhagen, Denmark
| | - Bo Zerahn
- Department of Clinical Physiology and Nuclear Medicine, Herlev Hospital, University of Copenhagen, Copenhagen, Denmark
| | - Jens Højberg
- Department of Cardiothoracic Anesthesiology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Egon Godthaab Hansen
- Department of Anesthesiology, Herlev Hospital, University of Copenhagen, Copenhagen, Denmark
| | - Lars Christian Gormsen
- Department of Clinical Physiology and Nuclear Medicine, Skejby Hospital, Aarhus University, Aarhus, Denmark
| | - Jacob Bejder
- Department of Nutrition, Exercise and Sports (NEXS), University of Copenhagen, Copenhagen, Denmark
| | - Thomas Krag
- Department of Neurology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - John Vissing
- Department of Neurology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Hans Erik Bøtker
- Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark
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Komisaruk BR, Frangos E. Vagus nerve afferent stimulation: Projection into the brain, reflexive physiological, perceptual, and behavioral responses, and clinical relevance. Auton Neurosci 2021; 237:102908. [PMID: 34823149 DOI: 10.1016/j.autneu.2021.102908] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 11/01/2021] [Accepted: 11/06/2021] [Indexed: 12/26/2022]
Abstract
The afferent vagus nerves project to diverse neural networks within the brainstem and forebrain, based on neuroanatomical, neurophysiological, and functional (fMRI) brain imaging evidence. In response to afferent vagal stimulation, multiple homeostatic visceral reflexes are elicited. Physiological stimuli and both invasive and non-invasive electrical stimulation that activate the afferent vagus elicit perceptual and behavioral responses that are of physiological and clinical significance. In the present review, we address these multiple roles of the afferent vagus under normal and pathological conditions, based on both animal and human evidence.
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Affiliation(s)
- Barry R Komisaruk
- Department of Psychology, Rutgers, The State University of New Jersey, Newark, NJ 07102, United States.
| | - Eleni Frangos
- National Center for Complementary and Integrative Health, National Institutes of Health, Bethesda, MD 20892, United States
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35
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Berthelsen LF, van Diepen S, Steele AR, Vanden Berg ER, Bird J, Thrall S, Skalk A, Byman B, Pentz B, Wilson RJA, Jendzjowsky NG, Day TA, Steinback CD. Duration at high altitude influences the onset of arrhythmogenesis during apnea. Eur J Appl Physiol 2021; 122:475-487. [PMID: 34800158 DOI: 10.1007/s00421-021-04842-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 11/04/2021] [Indexed: 10/19/2022]
Abstract
PURPOSE Autonomic control of the heart is balanced by sympathetic and parasympathetic inputs. Excitation of both sympathetic and parasympathetic systems occurs concurrently during certain perturbations such as hypoxia, which stimulate carotid chemoreflex to drive ventilation. It is well established that the chemoreflex becomes sensitized throughout hypoxic exposure; however, whether progressive sensitization alters cardiac autonomic activity remains unknown. We sought to determine the duration of hypoxic exposure at high altitude necessary to unmask cardiac arrhythmias during instances of voluntary apnea. METHODS Measurements of steady-state chemoreflex drive (SS-CD), continuous electrocardiogram (ECG) and SpO2 (pulse oximetry) were collected in 22 participants on 1 day at low altitude (1045 m) and over eight consecutive days at high-altitude (3800 m). SS-CD was quantified as ventilation (L/min) over stimulus index (PETCO2/SpO2). RESULTS Bradycardia during apnea was greater at high altitude compared to low altitude for all days (p < 0.001). Cardiac arrhythmias occurred during apnea each day but became most prevalent (> 50%) following Day 5 at high altitude. Changes in saturation during apnea and apnea duration did not affect the magnitude of bradycardia during apnea (ANCOVA; saturation, p = 0.15 and apnea duration, p = 0.988). Interestingly, the magnitude of bradycardia was correlated with the incidence of arrhythmia per day (r = 0.8; p = 0.004). CONCLUSION Our findings suggest that persistent hypoxia gradually increases vagal tone with time, indicated by augmented bradycardia during apnea and progressively increased the incidence of arrhythmia at high altitude.
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Affiliation(s)
- Lindsey F Berthelsen
- Neurovascular Health Lab, Faculty of Kinesiology, Sport, and Recreation, University of Alberta, 1-059A Li Ka Shing Centre for Health Research Innovation, 8602-112 St, Edmonton, AB, T6G 2E1, Canada
| | - Sean van Diepen
- Faculty of Medicine and Dentistry, Department of Critical Care and Division of Cardiology, Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - Andrew R Steele
- Neurovascular Health Lab, Faculty of Kinesiology, Sport, and Recreation, University of Alberta, 1-059A Li Ka Shing Centre for Health Research Innovation, 8602-112 St, Edmonton, AB, T6G 2E1, Canada
| | - Emily R Vanden Berg
- Neurovascular Health Lab, Faculty of Kinesiology, Sport, and Recreation, University of Alberta, 1-059A Li Ka Shing Centre for Health Research Innovation, 8602-112 St, Edmonton, AB, T6G 2E1, Canada
| | - Jordan Bird
- Department of Biology, Faculty of Science and Technology, Mount Royal University, Calgary, AB, Canada
| | - Scott Thrall
- Neurovascular Health Lab, Faculty of Kinesiology, Sport, and Recreation, University of Alberta, 1-059A Li Ka Shing Centre for Health Research Innovation, 8602-112 St, Edmonton, AB, T6G 2E1, Canada.,Department of Biology, Faculty of Science and Technology, Mount Royal University, Calgary, AB, Canada
| | - Alexandra Skalk
- Department of Biology, Faculty of Science and Technology, Mount Royal University, Calgary, AB, Canada
| | - Britta Byman
- Department of Biology, Faculty of Science and Technology, Mount Royal University, Calgary, AB, Canada
| | - Brandon Pentz
- Department of Biology, Faculty of Science and Technology, Mount Royal University, Calgary, AB, Canada
| | - Richard J A Wilson
- Department of Physiology and Pharmacology, University of Calgary, Calgary, AB, Canada
| | - Nicholas G Jendzjowsky
- The Lundquist Institute for Biomedical Innovation at Harbor, UCLA Medical Center, Torrance, CA, USA
| | - Trevor A Day
- Department of Biology, Faculty of Science and Technology, Mount Royal University, Calgary, AB, Canada
| | - Craig D Steinback
- Neurovascular Health Lab, Faculty of Kinesiology, Sport, and Recreation, University of Alberta, 1-059A Li Ka Shing Centre for Health Research Innovation, 8602-112 St, Edmonton, AB, T6G 2E1, Canada.
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Tso JV, Powers JM, Kim JH. Cardiovascular considerations for scuba divers. Heart 2021; 108:1084-1089. [PMID: 34670825 DOI: 10.1136/heartjnl-2021-319601] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 09/29/2021] [Indexed: 12/13/2022] Open
Abstract
As the popularity of scuba diving increases internationally, physicians interacting with divers in the clinical setting must be familiar with the cardiovascular stresses and risks inherent to this activity. Scuba presents a formidable cardiovascular challenge by combining unique environmental conditions with the physiologic demands of underwater exercise. Haemodynamic stresses encountered at depth include increased hydrostatic pressure leading to central shifts in plasma volume coupled with cold water stimuli leading to simultaneous parasympathetic and sympathetic autonomic responses. Among older divers and those with underlying cardiovascular risk factors, these physiologic changes increase acute cardiac risks while diving. Additional scuba risks, as a consequence of physical gas laws, include arterial gas emboli and decompression sickness. These pathologies are particularly dangerous with altered sensorium in hostile dive conditions. When present, the appropriate management of patent foramen ovale (PFO) is uncertain, but closure of PFO may reduce the risk of paradoxical gas embolism in divers with a prior history of decompression sickness. Finally, similar to other Masters-level athletes, divers with underlying traditional cardiovascular risk should undergo complete cardiac risk stratification to determine 'fitness-to-dive'. The presence of undertreated coronary artery disease, occult cardiomyopathy, channelopathy and arrhythmias must all be investigated and appropriately treated in order to ensure diver safety. A patient-centred approach facilitating shared decision-making between divers and experienced practitioners should be utilised in the management of prospective scuba divers.
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Affiliation(s)
- Jason V Tso
- Department of Cardiology, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Joshua M Powers
- Department of Cardiology, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Jonathan H Kim
- Department of Cardiology, Emory University School of Medicine, Atlanta, Georgia, USA
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McCulloch PF, Gebhart BW, Schroer JA. Large Lung Volumes Delay the Onset of the Physiological Breaking Point During Simulated Diving. Front Physiol 2021; 12:731633. [PMID: 34658915 PMCID: PMC8511405 DOI: 10.3389/fphys.2021.731633] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 09/10/2021] [Indexed: 11/13/2022] Open
Abstract
During breath holding after face immersion there develops an urge to breathe. The point that would initiate the termination of the breath hold, the "physiological breaking point," is thought to be primarily due to changes in blood gases. However, we theorized that other factors, such as lung volume, also contributes significantly to terminating breath holds during face immersion. Accordingly, nine naïve subjects (controls) and seven underwater hockey players (divers) voluntarily initiated face immersions in room temperature water at Total Lung Capacity (TLC) and Functional Residual Capacity (FRC) after pre-breathing air, 100% O2, 15% O2 / 85% N2, or 5% CO2 / 95% O2. Heart rate (HR), arterial blood pressure (BP), end-tidal CO2 (etCO2), and breath hold durations (BHD) were monitored during all face immersions. The decrease in HR and increase in BP were not significantly different at the two lung volumes, although the increase in BP was usually greater at FRC. BHD was significantly longer at TLC (54 ± 2 s) than at FRC (30 ± 2 s). Also, with each pre-breathed gas BHD was always longer at TLC. We found no consistent etCO2 at which the breath holding terminated. BDHs were significantly longer in divers than in controls. We suggest that during breath holding with face immersion high lung volume acts directly within the brainstem to actively delay the attainment of the physiological breaking point, rather than acting indirectly as a sink to produce a slower build-up of PCO2.
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Affiliation(s)
- Paul F. McCulloch
- Department of Physiology, College of Graduate Studies, Midwestern University, Downers Grove, IL, United States
| | - B. W. Gebhart
- Chicago College of Osteopathic Medicine, Midwestern University, Downers Grove, IL, United States
| | - J. A. Schroer
- Physical Therapy Program, College of Health Sciences, Midwestern University, Downers Grove, IL, United States
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Pla R, Poszalczyk G, Souaissia C, Joulia F, Guimard A. Underwater and Surface Swimming Parameters Reflect Performance Level in Elite Swimmers. Front Physiol 2021; 12:712652. [PMID: 34539436 PMCID: PMC8442910 DOI: 10.3389/fphys.2021.712652] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Accepted: 08/09/2021] [Indexed: 11/13/2022] Open
Abstract
Although the role of underwater phases is well-known, no study has taken an interest in describing and quantifying the distance and time spent in apnea as a condition for optimal performance. This study aimed to investigate the impact of time and distance spent underwater and surface parameters on the swimming performance of elite swimmers. The performances of 79 swimmers in 100-m freestyle were analyzed (short-course). The underwater and spatiotemporal parameters of three groups have been recorded: finalists of the 2018 World Swimming Championships (WORLD), French swimmers who reached a 100 m performance time under 50 s at the 2018 French National Championships (UND50), and those who reached a 100 m performance time above 50 s (UP50). The WORLD group spent more distance underwater (37.50 ± 4.92 m) in comparison with UND50 (31.90 ± 4.88 m, p < 0.05) and UP50 (31.94 ± 4.93 m, p < 0.01) groups. The total percentage of non-swimming time was higher for WORLD (39.11 ± 4.73%) vs. UND50 (34.21 ± 4.55%, p < 0.05) and UP50 (33.94 ± 5.00%, p < 0.01). In addition, underwater speed was higher for WORLD (2.54 ± 0.05 m/s) compared with UND50 (2.46 ± 0.09 m/s, p < 0.05) and UP50 (2.38 ± 0.11 m/s, p < 0.01). Three parameters among the underwater phases (i.e. distance underwater, speed underwater, and total percentage of non-swimming time) determine the 100-m freestyle short course performance. These data suggest an appropriate focus on specific apnea training to improve underwater skills during short-course swimming performances.
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Affiliation(s)
- Robin Pla
- French Swimming Federation, Clichy, France.,Institut de Recherche bioMédicale et d'Epidémiologie du Sport, IRMES, Paris, France
| | - Gauthier Poszalczyk
- Université Sorbonne Paris Nord, Hypoxie et Poumon, H&P, INSERM, UMR 1272, Bobigny, France.,Département STAPS, Université Sorbonne Paris Nord, Bobigny, France
| | - Cyrine Souaissia
- National Health Service (NHS) Grampian, Aberdeen Royal Infirmary, Aberdeen, United Kingdom
| | - Fabrice Joulia
- Center for Cardiovascular and Nutrition Research CV2N, Aix Marseille Université, INSERM 1263, INRAE 1260, Marseille, France
| | - Alexandre Guimard
- Université Sorbonne Paris Nord, Hypoxie et Poumon, H&P, INSERM, UMR 1272, Bobigny, France.,Département STAPS, Université Sorbonne Paris Nord, Bobigny, France
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Citherlet T, Crettaz von Roten F, Kayser B, Guex K. Acute Effects of the Wim Hof Breathing Method on Repeated Sprint Ability: A Pilot Study. Front Sports Act Living 2021; 3:700757. [PMID: 34514386 PMCID: PMC8424088 DOI: 10.3389/fspor.2021.700757] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 07/02/2021] [Indexed: 11/23/2022] Open
Abstract
The Wim Hof breathing method (WHBM) combines periods of hyperventilation (HV) followed by voluntary breath-holds (BH) at low lung volume. It has been increasingly adopted by coaches and their athletes to improve performance, but there was no published research on its effects. We determined the feasibility of implementing a single WHBM session before repeated sprinting performance and evaluated any acute ergogenic effects. Fifteen amateur runners performed a single WHBM session prior to a Repeated Ability Sprint Test (RAST) in comparison to voluntary HV or spontaneous breathing (SB) (control) in a randomized cross-over design. Gas exchange, heart rate, and finger pulse oxygen saturation (SpO2) were monitored. Despite large physiological effects in the SpO2 and expired carbon dioxide (VCO2) levels of both HV and WHBM, no significant positive or negative condition effects were found on RAST peak power, average power, or fatigue index. Finger SpO2 dropped to 60 ± 12% at the end of the BHs. Upon the last HV in the WHBM and HV conditions, end-tidal CO2 partial pressure (PETCO2) values were 19 ± 3 and 17 ± 3 mmHg, indicative of respiratory alkalosis with estimated arterial pH increases of +0.171 and of +0.181, respectively. Upon completion of RAST, 8 min cumulated expired carbon dioxide volumes in the WHBM and HV were greater than in SB, suggesting lingering carbon dioxide stores depletion. These findings indicate that despite large physiological effects, a single WHBM session does not improve anaerobic performance in repeated sprinting exercise.
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Affiliation(s)
- Tom Citherlet
- Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland
| | | | - Bengt Kayser
- Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland
| | - Kenny Guex
- School of Health Sciences, University of Applied Sciences and Arts Western Switzerland, Lausanne, Switzerland
- Swiss Athletics, Haus des Sports, Ittigen, Switzerland
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Annen J, Panda R, Martial C, Piarulli A, Nery G, Sanz LRD, Valdivia-Valdivia JM, Ledoux D, Gosseries O, Laureys S. Mapping the functional brain state of a world champion freediver in static dry apnea. Brain Struct Funct 2021; 226:2675-2688. [PMID: 34420066 DOI: 10.1007/s00429-021-02361-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 08/04/2021] [Indexed: 11/27/2022]
Abstract
Voluntary apnea showcases extreme human adaptability in trained individuals like professional free divers. We evaluated the psychological and physiological adaptation and the functional cerebral changes using electroencephalography (EEG) and functional Magnetic Resonance Imaging (fMRI) to 6.5 min of dry static apnea performed by a world champion free diver. Compared to resting state at baseline, breath holding was characterized by increased EEG power and functional connectivity in the alpha band, along with decreased delta band connectivity. fMRI connectivity was increased within the default mode network (DMN) and visual areas but decreased in pre- and postcentral cortices. While these changes occurred in regions overlapping with cerebral signatures of several meditation practices, they also display some unique features that suggest an altered somatosensory integration. As suggested by self-reports, these findings could reflect the ability of elite free divers to create a state of sensory dissociation when performing prolonged apnea.
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Affiliation(s)
- Jitka Annen
- Coma Science Group, GIGA Consciousness, University of Liège, Liège, Belgium.
- Centre du Cerveau, University Hospital of Liège, Liège, Belgium.
| | - Rajanikant Panda
- Coma Science Group, GIGA Consciousness, University of Liège, Liège, Belgium
- Centre du Cerveau, University Hospital of Liège, Liège, Belgium
| | - Charlotte Martial
- Coma Science Group, GIGA Consciousness, University of Liège, Liège, Belgium
- Centre du Cerveau, University Hospital of Liège, Liège, Belgium
| | - Andrea Piarulli
- Coma Science Group, GIGA Consciousness, University of Liège, Liège, Belgium
- Department of Surgical, Medical, Molecular and Critical Area Pathology, University of Pisa, Pisa, Italy
| | | | - Leandro R D Sanz
- Coma Science Group, GIGA Consciousness, University of Liège, Liège, Belgium
- Centre du Cerveau, University Hospital of Liège, Liège, Belgium
| | - Juan M Valdivia-Valdivia
- Department of Neurosurgery. St, Joseph's Hospital, Tampa, FL, USA
- International Association for Development of Apnea (AIDA International), Medical and Science Committee, Zurich, Switzerland
| | - Didier Ledoux
- Anesthesia and Intensive Care, GIGA Consciousness, ULiège, Liège, Belgium
- Intensive Care Department, University Hospital of Liège, Liège, Belgium
| | - Olivia Gosseries
- Coma Science Group, GIGA Consciousness, University of Liège, Liège, Belgium
- Centre du Cerveau, University Hospital of Liège, Liège, Belgium
| | - Steven Laureys
- Coma Science Group, GIGA Consciousness, University of Liège, Liège, Belgium
- Centre du Cerveau, University Hospital of Liège, Liège, Belgium
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Bouten J, De Bock S, Bourgois G, de Jager S, Dumortier J, Boone J, Bourgois JG. Heart Rate and Muscle Oxygenation Kinetics During Dynamic Constant Load Intermittent Breath-Holds. Front Physiol 2021; 12:712629. [PMID: 34366898 PMCID: PMC8339880 DOI: 10.3389/fphys.2021.712629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Accepted: 06/17/2021] [Indexed: 11/18/2022] Open
Abstract
Introduction: Acute apnea evokes bradycardia and peripheral vasoconstriction in order to conserve oxygen, which is more pronounced with face immersion. This response is contrary to the tachycardia and increased blood flow to muscle tissue related to the higher oxygen consumption during exercise. The aim of this study was to investigate cardiovascular and metabolic responses of dynamic dry apnea (DRA) and face immersed apnea (FIA). Methods: Ten female volunteers (17.1 ± 0.6 years old) naive to breath-hold-related sports, performed a series of seven dynamic 30 s breath-holds while cycling at 25% of their peak power output. This was performed in two separate conditions in a randomized order: FIA (15°C) and DRA. Heart rate and muscle tissue oxygenation through near-infrared spectroscopy were continuously measured to determine oxygenated (m[O2Hb]) and deoxygenated hemoglobin concentration (m[HHb]) and tissue oxygenation index (mTOI). Capillary blood lactate was measured 1 min after the first, third, fifth, and seventh breath-hold. Results: Average duration of the seven breath-holds did not differ between conditions (25.3 s ± 1.4 s, p = 0.231). The apnea-induced bradycardia was stronger with FIA (from 134 ± 4 to 85 ± 3 bpm) than DRA (from 134 ± 4 to 100 ± 5 bpm, p < 0.001). mTOI decreased significantly from 69.9 ± 0.9% to 63.0 ± 1.3% (p < 0.001) which is reflected in a steady decrease in m[O2Hb] (p < 0.001) and concomitant increase in m[HHb] (p = 0.001). However, this was similar in both conditions (0.121 < p < 0.542). Lactate was lower after the first apnea with FIA compared to DRA (p = 0.038), while no differences were observed in the other breath-holds. Conclusion: Our data show strong decreases in heart rate and muscle tissue oxygenation during dynamic apneas. A stronger bradycardia was observed in FIA, while muscle oxygenation was not different, suggesting that FIA did not influence muscle oxygenation. An order of mechanisms was observed in which, after an initial tachycardia, heart rate starts to decrease after muscle tissue deoxygenation occurs, suggesting a role of peripheral vasoconstriction in the apnea-induced bradycardia. The apnea-induced increase in lactate was lower in FIA during the first apnea, probably caused by the stronger bradycardia.
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Affiliation(s)
- Janne Bouten
- Department of Movement and Sports Sciences, Ghent University, Ghent, Belgium
| | - Sander De Bock
- Department of Movement and Sports Sciences, Ghent University, Ghent, Belgium
| | - Gil Bourgois
- Department of Movement and Sports Sciences, Ghent University, Ghent, Belgium
| | - Sarah de Jager
- Department of Movement and Sports Sciences, Ghent University, Ghent, Belgium
| | - Jasmien Dumortier
- Department of Movement and Sports Sciences, Ghent University, Ghent, Belgium
| | - Jan Boone
- Department of Movement and Sports Sciences, Ghent University, Ghent, Belgium.,Centre of Sports Medicine, Ghent University Hospital, Ghent, Belgium
| | - Jan G Bourgois
- Department of Movement and Sports Sciences, Ghent University, Ghent, Belgium.,Centre of Sports Medicine, Ghent University Hospital, Ghent, Belgium
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Abstract
BACKGROUND A typical oculocardiac reflex (OCR) is a moderate trigemino-vagal bradycardia elicited by tension on an extraocular muscle (EOM) during strabismus surgery; however, many other orbital stimuli can elicit cardiac slowing including retinopathy of prematurity examination. METHODS World literature related to trigeminovagal and oculocardiac reflex covering over 15,000 patients including 51 randomized clinical trials and case reports are analyzed and reviewed. Under an ongoing observational trial in Alaska, anesthetic, patient and surgical influences on routine strabismus surgery using prospective, uniform EOM tension are compared seeking sufficient sample size to characterize this individually widely variable cardiac response. RESULTS With adequate sample size, and emphasizing clinical studies controlling type of EOM, muscle tension amount and duration, anticholinergic and opioid medications, the following augment OCR; rapid-acting opioids and dexmedetomidine while OCR is reduced in older patients, the right eye, less EOM tension, deeper inhaled agents, hypocarbia, anticholinergic medications and orbital block. In re-operations, the former are relatively poor predictors of subsequent OCR. CONCLUSION Profound bradycardia can occur in almost 10% of strabismus surgery cases without anticholinergic preventive measures, but reliable prediction of OCR remains elusive. With foreknowledge and careful anesthetic monitoring of the patient before EOM manipulation, residual adverse sequelae from OCR are fortunately very rare. Despite well over a century of experience, the teleology for this occasionally dramatic cardiac response to eye surgery is still not known.
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Affiliation(s)
- Robert W Arnold
- The Alaska OCR Study, Alaska Blind Child Discovery, Alaska Children’s EYE & Strabismus, Anchorage, AK, 99508, USA
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43
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Peng H, Kawamura T, Akiyama H, Chang L, Iwata R, Muraoka I. Effects of sex differences on breath-hold diving performance. Respir Physiol Neurobiol 2021; 293:103721. [PMID: 34153544 DOI: 10.1016/j.resp.2021.103721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 05/16/2021] [Accepted: 06/17/2021] [Indexed: 10/21/2022]
Abstract
PURPOSE The present study aimed to measure diving response, CO2 sensitivity and forced vital capacity in male and female breath-hold divers (BHDs), and to determine their effect on breath-hold diving performance. METHODS This study included 8 non-divers (NDs, 4 males and 4 females) and 15 BHDs (7 males and 8 females). For NDs, diving response was measured during breath-holding with facial immersion, whereas for BHDs CO2 sensitivity was also measured. RESULTS Compared to NDs, BHDs showed a prominent diving response. In BHDs, no statistically significant sex differences were observed in diving response and CO2 sensitivity. Furthermore, a positive correlation was found between performance and the % forced vital capacity in BHDs. CONCLUSION It was suggested that % forced vital capacity contributed more significantly to performance than diving response and CO2 sensitivity. Furthermore, the higher performance of male divers compared to female divers may be due to the % forced vital capacity rather than the diving response and CO2 sensitivity.
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Affiliation(s)
- Heng Peng
- Graduate School of Sport Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa-city, Saitama, 359-1192, Japan.
| | - Takuji Kawamura
- Waseda Institute for Sport Sciences, 2-579-15 Mikajima, Tokorozawa-city, Saitama, 359-1192, Japan
| | - Hiroshi Akiyama
- National Institutes of Biomedical Innovation, Health and Nutrition, 1-23-1 Toyama, Shinjuku-ku, Tokyo, 162-8636, Japan
| | - Lili Chang
- Graduate School of Sport Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa-city, Saitama, 359-1192, Japan
| | - Risa Iwata
- Japan Institute of Sport Sciences, 3-15-1 Nishigaoka, Kita-ku, Tokyo, 115-0056, Japan
| | - Isao Muraoka
- Faculty of Sport Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa-city, Saitama, 359-1192, Japan
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44
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Physiology, pathophysiology and (mal)adaptations to chronic apnoeic training: a state-of-the-art review. Eur J Appl Physiol 2021; 121:1543-1566. [PMID: 33791844 PMCID: PMC8144079 DOI: 10.1007/s00421-021-04664-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 03/04/2021] [Indexed: 02/08/2023]
Abstract
Breath-hold diving is an activity that humans have engaged in since antiquity to forage for resources, provide sustenance and to support military campaigns. In modern times, breath-hold diving continues to gain popularity and recognition as both a competitive and recreational sport. The continued progression of world records is somewhat remarkable, particularly given the extreme hypoxaemic and hypercapnic conditions, and hydrostatic pressures these athletes endure. However, there is abundant literature to suggest a large inter-individual variation in the apnoeic capabilities that is thus far not fully understood. In this review, we explore developments in apnoea physiology and delineate the traits and mechanisms that potentially underpin this variation. In addition, we sought to highlight the physiological (mal)adaptations associated with consistent breath-hold training. Breath-hold divers (BHDs) are evidenced to exhibit a more pronounced diving-response than non-divers, while elite BHDs (EBHDs) also display beneficial adaptations in both blood and skeletal muscle. Importantly, these physiological characteristics are documented to be primarily influenced by training-induced stimuli. BHDs are exposed to unique physiological and environmental stressors, and as such possess an ability to withstand acute cerebrovascular and neuronal strains. Whether these characteristics are also a result of training-induced adaptations or genetic predisposition is less certain. Although the long-term effects of regular breath-hold diving activity are yet to be holistically established, preliminary evidence has posed considerations for cognitive, neurological, renal and bone health in BHDs. These areas should be explored further in longitudinal studies to more confidently ascertain the long-term health implications of extreme breath-holding activity.
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45
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Biggs EN, Budde R, Jefferys JGR, Irazoqui PP. Ictal activation of oxygen-conserving reflexes as a mechanism for sudden death in epilepsy. Epilepsia 2021; 62:752-764. [PMID: 33570173 PMCID: PMC9153691 DOI: 10.1111/epi.16831] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 01/04/2021] [Accepted: 01/11/2021] [Indexed: 01/05/2023]
Abstract
OBJECTIVE To test the hypothesis that death with physiological parallels to human cases of sudden unexpected death in epilepsy (SUDEP) can be induced in seizing rats by ictal activation of oxygen-conserving reflexes (OCRs). METHODS Urethane-anesthetized female Long-Evans rats were implanted with electrodes for electrocardiography (ECG), electrocorticography (ECoG), and respiratory thermocouple; venous and arterial cannulas; and a laryngoscope guide and cannula or nasal cannula for activation of the laryngeal chemoreflex (LCR) or mammalian diving reflex (MDR), respectively. Kainic acid injection, either systemic or into the ventral hippocampus, induced prolonged acute seizures. RESULTS Reflex challenges during seizures caused sudden death in 18 of 20 rats-all MDR rats (10) and all but two LCR rats (8) failed to recover from ictal activation of OCRs and died within minutes of the reflexes. By comparison, 4 of 4 control (ie, nonseizing) rats recovered from 64 induced diving reflexes (16 per rat), and 4 of 4 controls recovered from 64 induced chemoreflexes (16 per rat). Multiple measures were consistent with reports of human SUDEP. Terminal central apnea preceded terminal asystole in all cases. Heart and respiratory rate fluctuations that paralleled those seen in human SUDEP occurred during OCR-induced sudden death, and mean arterial pressure (MAP) was predictive of death, showing a 17 or 15 mm Hg drop (MDR and LCR, respectively) in the 20 s window centered on the time of brain death. OCR activation was never fatal in nonseizing rats. SIGNIFICANCE These results present a method of inducing sudden death in two seizure models that show pathophysiology consistent with that observed in human cases of SUDEP. This proposed mechanism directly informs previous findings by our group and others in the field; provides a repeatable, inducible animal model for the study of sudden death; and offers a potential explanation for observations made in cases of human SUDEP.
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Affiliation(s)
- Ethan N. Biggs
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
| | - Ryan Budde
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
| | - John G. R. Jefferys
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
- Department of Pharmacology, Oxford University, Oxford, UK
| | - Pedro P. Irazoqui
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
- Department of Electrical and Computer Engineering, Purdue University, West Lafayette, IN, USA
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46
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García I, Drobnic F, Javierre C, Pons V, Viscor G. Severe Hypoxic Exercise Does Not Impair Lung Diffusion in Elite Swimmers. High Alt Med Biol 2021; 22:90-95. [PMID: 33605802 DOI: 10.1089/ham.2020.0178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
García, Iker, Franchek Drobnic, Casimiro Javierre, Victoria Pons, and Ginés Viscor. Severe hypoxic exercise does not impair lung diffusion in elite swimmers. High Alt Med Biol. 22:90-95, 2021. Background: Exercise performed at high altitude may cause a subclinical pulmonary interstitial edema that can worsen gas exchange function. This study aimed to evaluate whether there are changes in alveolar-capillary diffusion after exercise during a short-term exposure to hypobaric hypoxia in elite swimmers. Materials and Methods: Seven elite swimmers (age: 20.4 ± 1.4 years, height: 1.78 ± 10.8 m, body mass: 69.7 ± 11.1 kg) participated in the study. Diffusing capacity of the lungs for carbon monoxide (DLCO), transfer coefficient of carbon monoxide, pulse oximeter oxygen saturation (SpO2), and heart rate (HR) were measured at sea level at rest (SL-R), and after a short-term hypobaric hypoxia exposure (4,000 m), both at rest (HA-R) and at the end of moderate interval exercise (HA-E). Results: The combined exposure to high altitude and exercise did not change DLCO from SL-R to HA-R, or HA-E (43.8 ± 9.8 to 41.3 ± 10.5 to 42.4 ± 8.6 ml minutes-1 mmHg-1, p = 0.391). As expected, elite swimmers showed large decrease in SpO2 (72 ± 5; p < 0.001) and increase in HR (139 ± 9 beats minutes-1; p < 0.003) after HA-E. Conclusions: An acute high-altitude exposure combined with submaximal exercise does not change alveolar-capillary diffusion in elite swimmers.
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Affiliation(s)
- Iker García
- Secció de Fisiologia, Departament de Biologia Cel·lular, Fisiologia i Immunologia, Facultat de Biologia, Universitat de Barcelona, Barcelona, Barcelona, Spain.,Departament de Fisiologia i Nutrició, Centre d'Alt Rendiment (CAR), Sant Cugat del Vallés, Barcelona, Spain
| | | | - Casimiro Javierre
- Departament de Ciències Fisiològiques, Facultat de Medicina, Universitat de Barcelona, Barcelona, Barcelona, Spain
| | - Victoria Pons
- Departament de Fisiologia i Nutrició, Centre d'Alt Rendiment (CAR), Sant Cugat del Vallés, Barcelona, Spain
| | - Ginés Viscor
- Secció de Fisiologia, Departament de Biologia Cel·lular, Fisiologia i Immunologia, Facultat de Biologia, Universitat de Barcelona, Barcelona, Barcelona, Spain
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47
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Cardiac hypoxic resistance and decreasing lactate during maximum apnea in elite breath hold divers. Sci Rep 2021; 11:2545. [PMID: 33510292 PMCID: PMC7844051 DOI: 10.1038/s41598-021-81797-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 01/06/2021] [Indexed: 01/30/2023] Open
Abstract
Breath-hold divers (BHD) enduring apnea for more than 4 min are characterized by resistance to release of reactive oxygen species, reduced sensitivity to hypoxia, and low mitochondrial oxygen consumption in their skeletal muscles similar to northern elephant seals. The muscles and myocardium of harbor seals also exhibit metabolic adaptations including increased cardiac lactate-dehydrogenase-activity, exceeding their hypoxic limit. We hypothesized that the myocardium of BHD possesses similar adaptive mechanisms. During maximum apnea 15O-H2O-PET/CT (n = 6) revealed no myocardial perfusion deficits but increased myocardial blood flow (MBF). Cardiac MRI determined blood oxygen level dependence oxygenation (n = 8) after 4 min of apnea was unaltered compared to rest, whereas cine-MRI demonstrated increased left ventricular wall thickness (LVWT). Arterial blood gases were collected after warm-up and maximum apnea in a pool. At the end of the maximum pool apnea (5 min), arterial saturation decreased to 52%, and lactate decreased 20%. Our findings contrast with previous MR studies of BHD, that reported elevated cardiac troponins and decreased myocardial perfusion after 4 min of apnea. In conclusion, we demonstrated for the first time with 15O-H2O-PET/CT and MRI in elite BHD during maximum apnea, that MBF and LVWT increases while lactate decreases, indicating anaerobic/fat-based cardiac-metabolism similar to diving mammals.
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48
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Kyriakoulis P, Kyrios M, Nardi AE, Freire RC, Schier M. The Implications of the Diving Response in Reducing Panic Symptoms. Front Psychiatry 2021; 12:784884. [PMID: 34912254 PMCID: PMC8667218 DOI: 10.3389/fpsyt.2021.784884] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 11/04/2021] [Indexed: 11/26/2022] Open
Abstract
Increased CO2 sensitivity is common in panic disorder (PD) patients. Free divers who are known for their exceptional breathing control have lower CO2 sensitivity due to training effects. This study aimed to investigate the immediate effects of cold facial immersion (CFI), breath holding and CO2 challenges on panic symptoms. Healthy participants and patients with PD were subjected to four experimental conditions in a randomly assigned order. The four conditions were (a) breath-holding (BH), (b) CFI for 30 s, (c) CO2 challenge, and (d) CO2 challenge followed by CFI. Participants completed a battery of psychological measures, and physiological data (heart rate and respiration rate) were collected following each experimental condition. Participants with PD were unable to hold their breath for as long as normal controls; however, this finding was not significant, potentially due to a small sample size. Significant reductions in both physiological and cognitive symptoms of panic were noted in the clinical group following the CFI task. As hypothesized, the CFI task exerted demonstrable anxiolytic effects in the clinical group in this study by reducing heart rate significantly and lessening self-reported symptoms of anxiety and panic. This outcome demonstrates the promise of the CFI task for clinical applications.
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Affiliation(s)
- Peter Kyriakoulis
- School of Health Sciences, Swinburne University of Technology, Hawthorn, VIC, Australia
| | - Michael Kyrios
- College of Education, Psychology & Social Work, Orama Institute for Mental Health & Wellbeing, Flinders University, Adelaide, SA, Australia
| | - Antonio Egidio Nardi
- Institute of Psychiatry-Federal University of Rio De Janeiro, Rio De Janeiro, Brazil
| | - Rafael C Freire
- Institute of Psychiatry-Federal University of Rio De Janeiro, Rio De Janeiro, Brazil.,Department of Psychiatry and Centre for Neuroscience Studies, Queen's University, Kingston, ON, Canada
| | - Mark Schier
- School of Health, Swinburne University, Hawthorn, VIC, Australia
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49
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Kuypers K, Martherus T, Lamberska T, Dekker J, Hooper SB, Te Pas AB. Reflexes that impact spontaneous breathing of preterm infants at birth: a narrative review. Arch Dis Child Fetal Neonatal Ed 2020; 105:675-679. [PMID: 32350064 DOI: 10.1136/archdischild-2020-318915] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 03/17/2020] [Accepted: 03/30/2020] [Indexed: 02/06/2023]
Abstract
Some neural circuits within infants are not fully developed at birth, especially in preterm infants. Therefore, it is unclear whether reflexes that affect breathing may or may not be activated during the neonatal stabilisation at birth. Both sensory reflexes (eg, tactile stimulation) and non-invasive ventilation (NIV) can promote spontaneous breathing at birth, but the application of NIV can also compromise breathing by inducing facial reflexes that inhibit spontaneous breathing. Applying an interface could provoke the trigeminocardiac reflex (TCR) by stimulating the trigeminal nerve resulting in apnoea and a reduction in heart rate. Similarly, airflow within the nasopharynx can elicit the TCR and/or laryngeal chemoreflex (LCR), resulting in glottal closure and ineffective ventilation, whereas providing pressure via inflations could stimulate multiple receptors that affect breathing. Stimulating the fast adapting pulmonary receptors may activate Head's paradoxical reflex to stimulate spontaneous breathing. In contrast, stimulating the slow adapting pulmonary receptors or laryngeal receptors could induce the Hering-Breuer inflation reflex or LCR, respectively, and thereby inhibit spontaneous breathing. As clinicians are most often unaware that starting primary care might affect the breathing they intend to support, this narrative review summarises the currently available evidence on (vagally mediated) reflexes that might promote or inhibit spontaneous breathing at birth.
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Affiliation(s)
- Kristel Kuypers
- Neonatology, Leiden University Medical Center, Leiden, The Netherlands
| | - Tessa Martherus
- Neonatology, Leiden University Medical Center, Leiden, The Netherlands
| | - Tereza Lamberska
- Neonatology, General University Hospital in Prague, Prague, Czech Republic
| | - Janneke Dekker
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, Australia.,Obstetrics and Gynaecology, Monash University, Clayton, Victoria, Australia
| | - Stuart B Hooper
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, Australia.,Obstetrics and Gynaecology, Monash University, Clayton, Victoria, Australia
| | - Arjan B Te Pas
- Neonatology, Leiden University Medical Center, Leiden, The Netherlands
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50
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Zenske A, Koch A, Kähler W, Oellrich K, Pepper C, Muth T, Schipke JD. Assessment of a dive incident using heart rate variability. Diving Hyperb Med 2020; 50:157-163. [PMID: 32557418 DOI: 10.28920/dhm50.2.157-163] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 02/23/2020] [Indexed: 12/11/2022]
Abstract
INTRODUCTION Scuba diving likely has an impact on the autonomic nervous system (ANS). In the course of conducting trials of underwater ECG recording for measurement of heart rate variability, there was an unexpected stressful event; one participant's regulator iced and began to free-flow. METHODS A custom-made, water- and pressure-tight aluminum housing was used to protect a portable Holter monitor. ECGs were recorded in three experienced divers who witnessed an unplanned moderately stressful incident during diving. The ECG signals were analysed for measures of heart rate variability (HRV). RESULTS Analysis for different short-term HRV measures provided consistent results if periods of interest were appropriately time-aligned. There was improvement in sympatho-vagal balance. One diver unexpectedly exhibited an increase in both sympathetic and vagal activity shortly after the incident. CONCLUSIONS A conventional open-water dive affected the ANS of experienced recreational divers as measured by HRV which provides a global evaluation of the ANS and alterations in its two branches. The heart rate variability data gathered from several participating divers around the time of this event illustrate the potential utility of this variable in quantifying stress during diving. HRV data may be useful in addressing relevant diving related questions such as effects of cold, exercise or different breathing gases on ANS function.
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Affiliation(s)
| | - Andreas Koch
- German Naval Medical Institute, Maritime Medicine, Kiel, Germany
| | - Wataru Kähler
- German Naval Medical Institute, Maritime Medicine, Kiel, Germany
| | - Kerstin Oellrich
- German Naval Medical Institute, Maritime Medicine, Kiel, Germany
| | - Clark Pepper
- Johanna Etienne Hospital, Dept. of Anaesthesiology, Neuss, Germany
| | - Thomas Muth
- Institute of Occupational, Social and Environmental Medicine, Heinrich Heine University, Düsseldorf, Germany
| | - Jochen D Schipke
- Forschungsgruppe Experimentelle Chirurgie, Universitäts-Klinikum, Düsseldorf, Germany.,Corresponding author: Professor Jochen D Schipke, c/o Forschungsgruppe Experimentelle Chirurgie, Universitäts-Klinikum Düsseldorf, DE, Moorenstrasse 5, D-40225 Düsseldorf,
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